Phosphor-containing film and backlight unit

ABSTRACT

A phosphor-containing film including a phosphor such as a quantum dot and is capable of suppressing the deterioration of the phosphor even where the film is formed into a laminated structure; and a backlight unit including the phosphor-containing film as a wavelength converting member. The film includes a phosphor-containing layer in which a plurality of fluorescent regions, each of which contains a phosphor that deteriorates through reaction with oxygen when exposed to oxygen, are discretely arranged and a resin layer having impermeability to oxygen is arranged among the plurality of the discretely arranged fluorescent regions; and a first substrate film and a second substrate film, which are respectively laminated on the both main surfaces of the phosphor-containing layer, in which the resin layer has a Knoop hardness of 115 N/mm2 to 285 N/mm2, a creep recovery rate of 22% or less, and an elastic recovery rate of 60% or more.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation of U.S. patent applicationSer. No. 16/287,256, filed on Feb. 27, 2019, which is a Continuation ofPCT International Application No. PCT/JP2017/031111 filed on Aug. 30,2017, which claims priority under 35 U.S.C. § 119(a) to Japanese PatentApplication No. 2016-172180, filed on Sep. 2, 2016, Japanese PatentApplication No. 2016-233275, filed on Nov. 30, 2016, and Japanese PatentApplication No. 2017-099573, filed on May 19, 2017. Each of the aboveapplications is hereby expressly incorporated by reference, in itsentirety, into the present application.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a phosphor-containing film containingphosphors that emit fluorescence upon irradiation with excitation lightand a backlight unit comprising the phosphor-containing film as awavelength converting member.

2. Description of the Related Art

Applications of a flat panel display such as a liquid crystal display(LCD) as a space-saving image display device with low power consumptionhave been widespread year by year. In recent liquid crystal displays,further power saving, an enhancement in color reproducibility, or thelike is required as an improvement in LCD performance.

Along with power saving of LCD backlight, in order to increase the lightutilization efficiency and improve the color reproducibility, it hasbeen proposed to use a wavelength converting layer containing a quantumdot (QD, also referred to as a quantum point) that converts a wavelengthof an incidence ray and emits the wavelength-converted light, as aluminescent material (phosphor).

The quantum dot has a state of an electron whose movement direction isrestricted in all directions three-dimensionally. In the case wherenanoparticles of a semiconductor are three-dimensionally surrounded by ahigh potential barrier, the nanoparticles become quantum dots. Thequantum dot expresses various quantum effects. For example, a “quantumsize effect” is expressed in which a density of electronic states(energy level) is discretized. According to this quantum size effect,the absorption wavelength and luminescence wavelength of light can becontrolled by changing the size of a quantum dot.

Generally, such quantum dots are dispersed in a resin or the like, andused as a quantum dot film for wavelength conversion, for example, bybeing disposed between a backlight and a liquid crystal panel.

In the case where excitation light is incident from a backlight to afilm containing quantum dots, the quantum dots are excited to emitfluorescence. Here, white light can be realized by using quantum dotshaving different luminescence properties and causing each quantum dot toemit light having a narrow half-width of red light, green light, or bluelight. Since the fluorescence by the quantum dot has a narrowhalf-width, wavelengths can be properly selected to thereby allow theresulting white light to be designed so that the white light is high inluminance and excellent in color reproducibility.

Meanwhile, there are problems that quantum dots are susceptible todeterioration due to moisture or oxygen, and particularly theluminescence intensity thereof decreases due to a photooxidationreaction. Therefore, the wavelength converting member is configured insuch a manner that gas barrier films are laminated on both main surfacesof a resin layer containing quantum dots (hereinafter, also referred toas a “quantum dot layer”) which is a wavelength converting layercontaining quantum dots, thereby protecting the quantum dot layer.

However, merely protecting both main surfaces of the quantum dot layerwith gas barrier films has a problem in which moisture or oxygen entersfrom the end face not protected by the gas barrier film, and thereforethe quantum dots deteriorate.

Therefore, it has been proposed to protect the entire periphery of thequantum dot layer with a barrier film.

For example, JP2010-061098A discloses a quantum point wavelengthconverting structure including a wavelength converting portioncontaining quantum points for wavelength-converting excitation light togenerate wavelength-converted light and a dispersion medium fordispersing the quantum points, and a sealing member for sealing thewavelength converting portion, in which the wavelength convertingportion is disposed between two sealing sheets which are sealingmembers, and the peripheries of the wavelength converting portion in thesealing sheets are heated and thermally adhered to each other, therebysealing the wavelength converting portion.

Further, JP2009-283441A discloses a light emitting device comprising acolor conversion layer (phosphor layer) for converting at least a partof color light emitted from a light source portion into another colorlight and a water impermeable sealing sheet for sealing the colorconversion layer, and discloses a color conversion sheet (phosphorsheet) in which penetration of water into the color conversion layer isprevented by a configuration where the sheet has a second bonding layerprovided in a frame shape along the outer periphery of the phosphorlayer, that is, so as to surround the planar shape of the colorconversion layer, and the second bonding layer is formed of an adhesivematerial having water vapor barrier properties.

Meanwhile, the wavelength converting layer containing quantum dots usedfor LCDs is a thin film of about 50 μm to 350 μm in thickness. There areproblems that it is extremely difficult to coat the entire end face ofsuch a very thin film with a sealing sheet such as a gas barrier film,thereby leading to poor productivity.

Such problems occur not only in quantum dots, but also in aphosphor-containing film comprising a phosphor which reacts with oxygenand deteriorates.

On the other hand, in order to produce a phosphor-containing filmcontaining a phosphor such as a quantum dot with high productionefficiency, preferred is a method of sequentially carrying out a coatingstep and a curing step on a long film by a roll-to-roll method to form alaminated structure and then cutting the resulting structure to adesired size.

However, in the case of obtaining a phosphor-containing film of adesired size by cutting from this long film, the phosphor-containinglayer is again exposed to the outside air at the cut end face, so it isnecessary to take measures against entry of oxygen from the cut endface.

On the other hand, US2015/048403A discloses an optical componentincluding two substrates, and a sealing material forming a plurality ofseparated regions, and a fluorescent member including a fluorescentsubstance arranged in the separated region that are laminated betweenthe two substrates, and also discloses that, by cutting at the sealingmaterial portion, the sealed state of the fluorescent member can bemaintained even in the case where the optical component is cut.

SUMMARY OF THE INVENTION

However, even in the case of a configuration in which the fluorescentmember is discretely arranged and sealed with a sealing material, it wasfound that there is a problem that cracks are generated in the sealingmaterial and therefore moisture and oxygen are likely to penetrate, inthe case where the optical component is cut.

The present invention has been made in view of the above circumstances,and an object of the present invention is to provide aphosphor-containing film which contains a phosphor such as a quantum dotand is capable of suppressing the deterioration of the phosphor even inthe case where the film is formed into a laminated structure, which isthen cut into a desired size; and a backlight unit comprising thephosphor-containing film as a wavelength converting member.

As a result of extensive studies to achieve the foregoing object, thepresent inventors have found that the foregoing object can be achievedby taking a configuration in which a phosphor-containing film includes aphosphor-containing layer in which a plurality of fluorescent regions,each of which contains a phosphor that deteriorates through a reactionwith oxygen in the case of being exposed to oxygen, are discretelyarranged and a resin layer having impermeability to oxygen is arrangedamong the plurality of discretely arranged fluorescent regions; and afirst substrate film laminated on one main surface of thephosphor-containing layer and a second substrate film laminated on theother main surface of the phosphor-containing layer, in which the resinlayer has a Knoop hardness of 115 N/mm² to 285 N/mm², a creep recoveryrate of 22% or less, and an elastic recovery rate of 60% or more. Thepresent invention has been completed based on these findings.

That is, it has been found that the foregoing object can be achieved bythe following configuration.

(1) A phosphor-containing film comprising:

a phosphor-containing layer in which a plurality of fluorescent regions,each of which contains a phosphor that deteriorates through a reactionwith oxygen in the case of being exposed to oxygen, are discretelyarranged and a resin layer having impermeability to oxygen is arrangedamong the plurality of discretely arranged fluorescent regions; and afirst substrate film laminated on one main surface of thephosphor-containing layer and a second substrate film laminated on theother main surface of the phosphor-containing layer, in which the resinlayer has a Knoop hardness of 115 N/mm² to 285 N/mm², a creep recoveryrate of 22% or less, and an elastic recovery rate of 60% or more.

(2) The phosphor-containing film according to (1), in which the regionlosing the fluorescence properties and the resin layer are exposed onthe end face of the phosphor-containing film.

(3) The phosphor-containing film according to (1) or (2), in which theresin layer has an oxygen permeability of 10 cc/(m²·day·atm) or less.

(4) The phosphor-containing film according to any one of (1) to (3), inwhich the oxygen permeability of the first substrate film and the secondsubstrate film is 1 cc/(m²·day·atm) or less.

(5) The phosphor-containing film according to any one of (1) to (4), inwhich a resin contained in the resin layer is formed of a compositioncontaining a compound having a photopolymerizable functional group or athermopolymerizable functional group.

(6) A backlight unit comprising:

a wavelength converting member including the phosphor-containing filmaccording to any one of (1) to (5), and

at least one of a blue light emitting diode or an ultraviolet lightemitting diode.

According to the present invention, it is possible to provide aphosphor-containing film which contains a phosphor such as a quantum dotand is capable of suppressing the deterioration of the phosphor even inthe case where the film is formed into a laminated structure, which isthen cut into a desired size; and a backlight unit comprising thephosphor-containing film as a wavelength converting member.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view schematically showing an example of aphosphor-containing film of the present invention.

FIG. 2 is a plan view of the phosphor-containing film of FIG. 1.

FIG. 3 is a cross-sectional view of the phosphor-containing film of FIG.1.

FIG. 4 is a plan view showing another example of a plan view pattern ofa fluorescent region.

FIG. 5 is a plan view showing still another example of the plan viewpattern of the fluorescent region.

FIG. 6 is a diagram for explaining a method of specifying a contour ofthe fluorescent region.

FIG. 7A is a plan view schematically showing another example of thephosphor-containing film of the present invention.

FIG. 7B is a cross-sectional view taken along a line B-B of FIG. 7A.

FIG. 7C is a cross-sectional view taken along a line C-C of FIG. 7A.

FIG. 8A is a plan view schematically showing still another example ofthe phosphor-containing film of the present invention.

FIG. 8B is a cross-sectional view taken along a line B-B of FIG. 8A.

FIG. 9A is a plan view schematically showing still another example ofthe phosphor-containing film of the present invention.

FIG. 9B is a cross-sectional view taken along a line B-B of FIG. 9A.

FIG. 10 is a view showing a production step of the phosphor-containingfilm.

FIG. 11 is a schematic view for explaining a method for producing thephosphor-containing film of the present invention.

FIG. 12 is a schematic view for explaining the method for producing thephosphor-containing film of the present invention.

FIG. 13 is a cross-sectional view of a schematic configuration of abacklight unit comprising the phosphor-containing film as a wavelengthconverting member.

FIG. 14 is a cross-sectional view of a schematic configuration of aliquid crystal display comprising the backlight unit.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of a phosphor-containing film and a backlightunit comprising the phosphor-containing film according to the presentinvention will be described with reference to the accompanying drawings.In the drawings of the present specification, the scale of each part isappropriately changed for easy visual recognition. In the presentspecification, the numerical range expressed by using “to” means a rangeincluding numerical values described before and after “to” as a lowerlimit value and an upper limit value, respectively.

<Phosphor-Containing Film>

The phosphor-containing film according to the embodiment of the presentinvention is a phosphor-containing film including:

a phosphor-containing layer in which a plurality of fluorescent regions,each of which contains a phosphor that deteriorates through a reactionwith oxygen in the case of being exposed to oxygen, are discretelyarranged and a resin layer having impermeability to oxygen is arrangedamong the plurality of discretely arranged fluorescent regions; and

a first substrate film laminated on one main surface of thephosphor-containing layer and a second substrate film laminated on theother main surface of the phosphor-containing layer,

in which the resin layer has a Knoop hardness of 115 N/mm² to 285 N/mm²,a creep recovery rate of 22% or less, and an elastic recovery rate of60% or more.

FIG. 1 is a perspective view schematically showing an example of aphosphor-containing film 1 according to the embodiment of the presentinvention, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is across-sectional view of FIG. 1. In FIG. 1, a second substrate film 20 isindicated by a broken line and a phosphor-containing layer 30 isindicated by a solid line for the purpose of explanation.

The phosphor-containing film 1 of the present embodiment comprises afirst substrate film 10, a phosphor-containing layer 30 in which aplurality of regions 35 containing phosphors 31 which deteriorates bybeing reacted with oxygen upon exposure to oxygen are discretelyarranged on the first substrate film 10, and a resin layer 38 havingimpermeability to oxygen is disposed between the discretely arrangedregions 35 containing phosphors 31, and a second substrate film 20disposed on the phosphor-containing layer 30. Hereinafter, the region 35containing the phosphors 31 may be referred to as a fluorescent region35 in some cases.

In the present specification, the phrase “a plurality of regionscontaining phosphors . . . are discretely arranged on the firstsubstrate film” means that, as shown in FIGS. 1 and 2, in the case ofbeing viewed from the direction perpendicular to the film surface of thefirst substrate film (in plan view), a plurality of fluorescent regions35 are disposed in isolation without contacting each other in thetwo-dimensional direction along the film surface of the first substratefilm 10. In the present example, the fluorescent regions 35 are in theform of a cylinder (disk), and each fluorescent region 35 is isolatedlysurrounded by a resin layer 38 having impermeability to oxygen in thetwo-dimensional direction along the film surface of the first substratefilm 10, and the penetration of oxygen from the two-dimensionaldirection along the film surface of the first substrate film 10 into theindividual fluorescent regions 35 is blocked.

In the present specification, the phrase, “having impermeability tooxygen” means that an oxygen permeability is 10 cc/(m²·day·atm) or less.The oxygen permeability of the resin layer having impermeability tooxygen is more preferably 1 cc/(m²·day·atm) or less and still morepreferably 10⁻¹ cc/(m²·day·atm) or less. The phrase “havingimpermeability” and the phrase “having barrier properties” in thepresent specification are used synonymously. That is, in the presentspecification, a gas barrier means having impermeability to a gas, and awater vapor barrier means having impermeability to water vapor. Further,a layer having impermeability to both of oxygen and water vapor isreferred to as a “barrier layer”.

In the phosphor-containing film 1 according to the embodiment of thepresent invention, since the fluorescent regions 35 are discretelyarranged in the two-dimensional direction, as shown in FIG. 2, assumingthat the phosphor-containing film 1 is a part of a long film, whicheverportion is linearly cut as indicated by the broken line, the fluorescentregion 35 other than the fluorescent region 35 which is the cut point issurrounded by the resin layer 38, and thus can be kept in a sealedstate. In addition, the fluorescent region 35 that has been cut andexposed to outside air loses its function as an original phosphor, butthe region losing the fluorescence properties becomes a resin layer thatprotects the fluorescent region 35 not exposed to outside air from theoutside air.

Here, in the phosphor-containing film according to the embodiment of thepresent invention, the resin layer has a Knoop hardness of 115 N/mm² to285 N/mm², a creep recovery rate of 22% or less, and an elastic recoveryrate of 60% or more.

As described above, in order to produce a phosphor-containing filmcontaining a phosphor such as a quantum dot with high productionefficiency, preferred is a method in which a coating step and a curingstep are sequentially carried out on a long film by a roll-to-rollmethod to form a laminated structure which is then cut into a desiredsize. In the case where a phosphor-containing film of a desired size iscut from this long film, the phosphor-containing layer is exposed to theoutside air at the cut end face, so it is necessary to take measuresagainst the penetration of oxygen from the cut end face.

Therefore, by taking a configuration in which phosphors such as quantumdots are discretely arranged in a plurality of regions and a sealingmaterial is arranged around the phosphors, it is considered to keep thesealed state of the fluorescent member even in the case where theoptical component is cut, by cutting the film at the part of the sealingmaterial at the time of cutting the phosphor-containing film.

However, even in the case of a configuration such that the phosphors arediscretely arranged and sealed with a sealing material, it was foundthat there is a problem that cracks are generated in the sealingmaterial and therefore moisture and oxygen are likely to penetrate, atthe time of cutting the phosphor-containing film.

In contrast, the phosphor-containing film according to the embodiment ofthe present invention is configured such that the resin layer, which isa sealing material, has a Knoop hardness of 115 N/mm² to 285 N/mm², acreep recovery rate of 22% or less, and an elastic recovery rate of 60%or more, so that cracking of the resin layer (sealing material) at thetime of cutting the phosphor-containing film can be suppressed, andpenetration of moisture and oxygen from the end face in thephosphor-containing film after cutting thereof can be suppressed,resulting in suppression of deterioration of the phosphor.

More specifically, the resin layer exhibiting a Knoop hardness of 115N/mm² to 285 N/mm² on at least one surface and preferably on bothsurfaces thereof can exhibit good results in cutting. The indentation ofa Knoop indenter in the case of measuring the Knoop hardness can mainlysimulate the penetration of a cutting blade. Therefore, in the casewhere the Knoop hardness is too small, micro scratches also occur in adirection different from the direction in which cutting is desired, thuscausing cracks, and in the case where the Knoop hardness is too large,it is considered that the load by the cutting blade is insufficient andtherefore the cut remainder appears.

From the viewpoint of further improving the cutting ability, the Knoophardness is preferably 140 N/mm² to 285 N/mm².

The Knoop hardness in the present invention is a value obtained by thefollowing method.

Using a PICODENTOR HM500p type hardness tester manufactured by FischerInstruments K.K., the surface of a sample fixed to a glass substrate ismeasured with a Knoop indenter under the conditions of a load time of 10sec, a creep time under a maximum load of 5 sec, an unloading time of 10sec, a creep time after unloading of 5 sec, and a maximum load of 20 mN.The hardness is calculated from the relationship between theindenter-sample contact area obtained from the indentation depth and themaximum load, and the average value of values at 10 points is taken asthe Knoop hardness.

The resin layer exhibiting a creep recovery rate of 22% or less on atleast one surface and preferably on both surfaces thereof can exhibitgood results in cutting. The creep recovery rate represents the recoveryrate of the indentation depth after unloading following the indentationof the Knoop indenter, which corresponds to a deformation amountobtained by subtracting the “elastic recovery portion” and the “plastic(permanent) deformation portion in which the bond is broken” from themaximum indentation depth, and corresponds to the viscoelasticdeformation. In the case where the viscoelastic deformation is large, apart of the work given by indentation is wastefully consumed, and evenin the case where the same force is given, plastic (permanent)deformation does not proceed as compared with the case whereviscoelastic deformation is small Therefore, it is considered that, inthe case where the creep recovery rate is too high, the viscoelasticbehavior will appear and consequently the cut remainder appears.

From the viewpoint of further improving the cutting ability, the creeprecovery rate is preferably 20% or less.

The creep recovery rate in the present invention is a value obtained bythe following method.

Using a PICODENTOR HM500p type hardness tester manufactured by FischerInstruments K.K., the surface of a sample fixed to a glass substrate ismeasured with a Knoop indenter under the conditions of a load time of 10sec, a creep time under a maximum load of 5 sec, an unloading time of 10sec, a creep time after unloading of 5 sec, and a maximum load of 20 mN.The ratio of creep recovery is calculated from the relationship betweenthe indentation depth immediately after unloading and the depth after 5seconds of unloading, and the average value of values at 10 points istaken as the creep recovery rate.

The resin layer exhibiting an elastic recovery rate of 60% or more on atleast one surface and preferably on both surfaces thereof can exhibitgood results in cutting. The elastic recovery rate represents adeformation recovery rate until the load becomes zero from the maximumload of the Knoop indenter. Unlike creep recovery, the elastic recoveryrate corresponds to an amount of deformation recovery instantaneouslyimmediately after unloading. In the case where the elastic recovery rateis small against creep recovery, recovery of deformation due toindentation is delayed. Therefore, in the case where the elasticrecovery rate is too small, shape recovery after cutting is delayed,resulting in film thickness unevenness, which is considered to lead toluminance unevenness.

From the viewpoint of further improving the cutting ability, the elasticrecovery rate is preferably 65% or more.

The elastic recovery rate in the present invention is a value obtainedby the following method.

Using a PICODENTOR HM500p type hardness tester manufactured by FischerInstruments K.K., the surface of a sample fixed to a glass substrate ismeasured with a Knoop indenter under the conditions of a load time of 10sec, a creep time under a maximum load of 5 sec, an unloading time of 10sec, a creep time after unloading of 5 sec, and a maximum load of 20 mN.The ratio of elastic recovery is calculated from the relationshipbetween the area surrounded by three points of [indentation depth aftercreep time, maximum load], [indentation depth after creep time, zeroload], and [indentation depth immediately after unloading, zero load](corresponding to elastic deformation energy E released at unloading),and the area surrounded by four points of the origin, [indentation depthbefore creep time, maximum load], [indentation depth after creep time,maximum load], and [indentation depth after creep time, zero load](corresponding to the total energy E required for load (and creep)), onthe graph obtained by plotting the horizontal axis as an indentationdepth and the vertical axis as a load, and the average value of valuesat 10 points is taken as the elastic recovery rate.

Here, in particular, in the case where cutting is carried out across theresin layer and the fluorescent region, there are cases where cracks arelikely to occur in the resin layer due to a difference in hardnessbetween the resin layer and the fluorescent region or the like. However,cracking of the resin layer at the time of cutting can be suitablysuppressed by setting the Knoop hardness, the creep recovery rate, andthe elastic recovery rate of the resin layer to the above ranges.

Further, in the phosphor-containing film according to the embodiment ofthe present invention, cracking of the resin layer can be suitablysuppressed even in the case where cutting is carried out across theresin layer and the fluorescent region, so that the cut point can befreely selected, and the degree of freedom in the size and shape at thetime of cutting is high.

In addition, in the case where cutting is carried out across the resinlayer and the fluorescent region, the phosphor-containing film has aconfiguration in which the region losing the fluorescence properties andthe resin layer are exposed at the end face which is the cut surface. Inaddition, in the case where the fluorescent region is cut across aplurality of regions, the phosphor-containing film has a configurationin which the region losing the fluorescence properties and the resinlayer are alternately exposed at the end face of the phosphor-containingfilm.

Here, the fluorescent region 35 is formed by dispersing the phosphors 31in a binder 33. In the case where the oxygen permeability of the binder33 is larger than the permeability of the resin layer 38 filled betweenthe fluorescent regions 35, that is, in the case where the binder 33tends to permeate oxygen, the effects of the present invention areparticularly remarkable.

Further, the first substrate film 10 and the second substrate film 20are preferably impermeable to oxygen and may have a laminated structureof a support film (11, 21) and a barrier layer (12, 22) havingimpermeability to oxygen as shown in FIG. 3.

In addition, the size and arrangement pattern of the fluorescent region35 are not particularly limited and may be appropriately designedaccording to desired conditions. In designing, geometric constraints forarranging the fluorescent regions spaced apart from each other in planview, allowable values of the width of the non-light emitting regiongenerated at the time of cutting, and the like are taken intoconsideration. Further, for example, in the case where the printingmethod is used as one of the methods for forming a fluorescent region tobe described later, there is also a restriction that printing cannot becarried out unless the individual occupied area (in plan view) is notless than a certain size. Furthermore, the shortest distance betweenadjacent fluorescent regions is required to be a distance capable ofachieving an oxygen permeability of 10 cc/(m²·day·atm) or less. Inconsideration of these factors, a desired shape, size, and arrangementpattern may be designed.

In the above embodiment, the fluorescent region 35 is cylindrical and iscircular in plan view, but the shape of the fluorescent region 35 is notparticularly limited. The fluorescent region 35 may be a polygonal prismsuch as a quadrangular in plan view as shown in FIG. 4, or a hexagon inplan view as shown in FIG. 5. In the above example, the bottom surfaceof the cylinder or the polygonal prism is disposed parallel to thesubstrate film surface, but the bottom surface may not necessarily bedisposed parallel to the substrate film surface. Further, the shape ofeach fluorescent region 35 may be amorphous.

In the case where the boundary between the binder 33 in the fluorescentregion 35 and the resin layer 38 being impermeable to oxygen and beingbetween the fluorescent regions 35 is not clear, as shown in FIG. 6, aline connecting the points on the outside (the side on which thephosphor 31 is not disposed) of the phosphor 31 e positioned at theoutermost position of the region where the phosphor 31 is closelydisposed is considered as the contour m of the fluorescent region 35(the boundary between the fluorescent region 35 and the resin layer 38).The position of the phosphor can be specified by irradiation of thephosphor-containing layer with excitation light to cause the phosphor toemit light, followed by observation with, for example, a confocal lasermicroscope or the like, whereby the contour m of the fluorescent region35 can be specified. In the present specification, the side of acylinder or a polygonal prism is allowed to meander like the contour inFIG. 6.

In the above embodiment, the fluorescent region 35 is periodicallydisposed in a pattern, but it may be non-periodic as long as the desiredperformance is not impaired in the case where a plurality of fluorescentregions 35 are discretely arranged. It is preferable that thefluorescent region 35 is uniformly distributed over the entire region ofthe phosphor-containing layer 30 because the in-plane distribution ofluminance is uniform.

In order to obtain a sufficient amount of fluorescence, it is desirableto make the region occupied by the fluorescent region 35 as large aspossible.

The phosphor 31 in the fluorescent region 35 may be of one kind or ofplural kinds. In addition, the phosphor 31 in one fluorescent region 35is regarded as one kind, and a region containing a first phosphor and aregion containing a second phosphor different from the first phosphoramong the plurality of fluorescent regions 35 may be disposedperiodically or non-periodically. The kind of the phosphor may be threeor more.

The phosphor-containing layer 30 may be formed by laminating a pluralityof fluorescent regions 35 in the thickness direction of the film. Suchan example will be briefly described with reference to FIGS. 7A to 9B.In the following description, the same elements as those of thephosphor-containing film 1 shown in FIG. 1 are denoted by the samereference numerals, and a detailed description thereof will be omitted.

FIG. 7A is a schematic plan view of another example of thephosphor-containing film, FIG. 7B is a cross-sectional view taken alonga line B-B of FIG. 7A, and FIG. 7C is a cross-sectional view taken alonga line C-C of FIG. 7A.

The phosphor-containing film 3 shown in FIGS. 7A to 7C comprises, as afluorescent region, a first fluorescent region 35 a in which the firstphosphors 31 a are dispersed in the binder 33 and a second fluorescentregion 35 b in which the second phosphors 31 b different from the firstphosphors 31 a are dispersed in the binder 33. The first fluorescentregion 35 a and the second fluorescent region 35 b are alternatelydisposed in plan view and are dispersedly arranged at differentpositions in the film thickness direction. The first fluorescent region35 a is disposed on the main surface side adjacent to the secondsubstrate film 20 and the second fluorescent region 35 b is disposed onthe main surface side adjacent to the first substrate film 10, and thefirst fluorescent region 35 a and the second fluorescent region 35 b aredisposed so as not to overlap each other in plan view.

The first phosphor 31 a and the second phosphor 31 b are, for example,phosphors having luminescence center wavelengths different from eachother. For example, a phosphor having a luminescence center wavelengthin a wavelength range of 600 to 680 nm is used as the first phosphor 31a, and a phosphor having a luminescence center wavelength in awavelength range of 520 to 560 nm is used as the second phosphor 31 b,and so on.

Although the binder 33 of the first fluorescent region 35 a and thesecond fluorescent region 35 b is made of the same composition in thepresent example, it may be made of a different composition.

FIG. 8A is a plan view schematically showing another example of thephosphor-containing film according to the embodiment of the presentinvention, and FIG. 8B is a cross-sectional view taken along a line B-Bof FIG. 8A.

The phosphor-containing film 4 shown in FIGS. 8A and 8B is differentfrom the phosphor-containing film 3 shown in FIGS. 7A to 7C in that thefirst fluorescent region 35 a and the second fluorescent region 35 bdisposed at different positions in the film thickness directionpartially overlap each other in the case where the film surface isviewed in plan view. In this manner, the first fluorescent region 35 aand the second fluorescent region 35 b disposed at different positionsin the film direction may overlap each other in plan view.

FIG. 9A is a plan view schematically showing another example of thephosphor-containing film according to the embodiment of the presentinvention, and FIG. 9B is a cross-sectional view taken along a line B-Bof FIG. 9A.

The phosphor-containing film 6 shown in FIGS. 9A and 9B comprises astep-like fluorescent region 35 in which quadrangular prism-shapedregions are laminated with a shift of a half cycle. In the fluorescentregion 35, the first phosphors 31 a and the second phosphors 31 b aredispersed in the binder 33. In the present example, the second phosphors31 b are dispersed in the lower step portion of the step-likefluorescent region 35 and the first phosphors 31 a are dispersed in theupper step portion of the step-like fluorescent region 35, but the firstphosphors 31 a and the second phosphors 31 b may be mixed in the entireupper and lower step portions in the fluorescent region 35.

As described above, in the phosphor-containing film according to theembodiment of the present invention, the shape of the fluorescent region35 and the arrangement pattern thereof are not particularly limited. Thefluorescent regions are discretely arranged on the film surface in anycase, so that the phosphor in the fluorescent region at the cut endportion deteriorates but the fluorescent region in the portion otherthan the cut end portion is sealed by being surrounded with anoxygen-impermeable resin in the direction along the film surface.Consequently, it is possible to suppress deterioration in performancedue to the penetration of oxygen from the direction along the filmsurface.

Hereinafter, individual constituent elements of the phosphor-containingfilm according to the embodiment of the present invention will bedescribed.

The phosphor-containing film 1 takes a configuration in which thephosphor-containing layer 30 is laminated on one film surface of thefirst substrate film 10, the second substrate film 20 is laminated onthe phosphor-containing layer 30, and the phosphor-containing layer 30is sandwiched between two substrate films 10 and 20.

—Phosphor-Containing Layer—

The phosphor-containing layer 30 comprises a fluorescent region 35containing a plurality of phosphors 31 and a resin layer 38 impermeableto oxygen and filled between the fluorescent regions 35.

<<Region Containing Phosphors (Fluorescent Region)>>

The fluorescent region 35 is constituted of phosphors 31 and a binder 33in which the phosphors 31 are dispersed and is formed by applying andcuring a coating liquid for forming a fluorescent region containing thephosphors 31 and a curable compound.

<Phosphor>

Various known phosphors can be used as a phosphor which deteriorates bybeing reacted with oxygen upon exposure to oxygen. Examples of thephosphor include inorganic phosphors such as rare earth doped garnet,silicates, aluminates, phosphates, ceramic phosphors, sulfide phosphors,and nitride phosphors, and organic fluorescent substances includingorganic fluorescent dyes and organic fluorescent pigments. In addition,phosphors with rare earth-doped semiconductor fine particles, andsemiconductor nanoparticles (quantum dots and quantum rods) are alsopreferably used. A single kind of phosphor may be used alone, but aplurality of phosphors having different wavelengths may be mixed andused so as to obtain a desired fluorescence spectrum, or a combinationof phosphors of different material constitutions (for example, acombination of a rare earth doped garnet and quantum dots) may be used.

As used herein, the phrase “exposure to oxygen” means exposure to anenvironment containing oxygen, such as in the atmosphere, and the phrase“deteriorates by being reacted with oxygen” means that the phosphor isoxidized so that the performance of the phosphor deteriorates(decreases) and refers to mainly the luminescence performance decliningas compared with that before the reaction with oxygen, and in the casewhere the phosphor is used as a photoelectric conversion element, such aphrase means that the photoelectric conversion efficiency declines ascompared with that before the reaction with oxygen.

In the following description, as a phosphor deteriorating by oxygen,mainly quantum dots will be described as an example. However, thephosphor of the present invention is not limited to quantum dots and isnot particularly limited as long as it is a fluorescent coloring agentthat deteriorates due to oxygen, or a material that converts energy fromthe outside into light or converts light into electricity, such as aphotoelectric conversion material.

(Quantum Dot)

The quantum dot is a fine particle of a compound semiconductor having asize of several nm to several tens of nm and is at least excited byincident excitation light to emit fluorescence.

The phosphor of the present embodiment may include at least one quantumdot or may include two or more quantum dots having differentluminescence properties. Known quantum dots include a quantum dot (A)having a luminescence center wavelength in a wavelength range of 600 nmor more and 680 nm or less, a quantum dot (B) having a luminescencecenter wavelength in a wavelength range of 500 nm or more to less than600 nm, and a quantum dot (C) having a luminescence center wavelength ina wavelength range of 400 nm or more to less than 500 nm, and thequantum dot (A) is excited by excitation light to emit red light, thequantum dot (B) is excited by excitation light to emit green light, andthe quantum dot (C) is excited by excitation light to emit blue light.For example, in the case where blue light is incident as excitationlight to a phosphor-containing layer containing the quantum dot (A) andthe quantum dot (B), red light emitted from the quantum dot (A), greenlight emitted from the quantum dot (B) and blue light permeating throughthe phosphor-containing layer can realize white light. Alternatively,ultraviolet light can be incident as excitation light to aphosphor-containing layer containing the quantum dots (A), (B), and (C),thereby allowing red light emitted from the quantum dot (A), green lightemitted from the quantum dot (B), and blue light emitted from thequantum dot (C) to realize white light.

With respect to the quantum dot, reference can be made to, for example,paragraphs [0060] to [0066] of JP2012-169271A, but the quantum dot isnot limited to those described therein. As the quantum dot, commerciallyavailable products can be used without any limitation. The luminescencewavelength of the quantum dot can usually be adjusted by the compositionand size of the particles.

The quantum dot can be added in an amount of, for example, about 0.1 to10 parts by mass with respect to 100 parts by mass of the total amountof the coating liquid.

The quantum dots may be added into the coating liquid in the form ofparticles or in the form of a dispersion liquid in which the quantumdots are dispersed in an organic solvent. It is preferable that thequantum dots be added in the form of a dispersion liquid, from theviewpoint of suppressing aggregation of quantum dot particles. Theorganic solvent used for dispersing the quantum dots is not particularlylimited.

As the quantum dots, for example, core-shell type semiconductornanoparticles are preferable from the viewpoint of improving durability.As the core, Group II-VI semiconductor nanoparticles, Group III-Vsemiconductor nanoparticles, multi-component semiconductornanoparticles, and the like can be used. Specific examples thereofinclude, but are not limited to, CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, InP,InAs, and InGaP. Among them, CdSe, CdTe, InP, InGaP are preferable fromthe viewpoint of emitting visible light with high efficiency. As theshell, CdS, ZnS, ZnO, GaAs, and complexes thereof can be used, but it isnot limited thereto. The luminescence wavelength of the quantum dot canusually be adjusted by the composition and size of the particles.

The quantum dot may be a spherical particle or may be a rod-likeparticle also called a quantum rod, or may be a tetrapod-type particle.A spherical quantum dot or rod-like quantum dot (that is, a quantum rod)is preferable from the viewpoint of narrowing a full width at halfmaximum (FWHM) and enlarging the color reproduction range of a liquidcrystal display.

A ligand having a Lewis basic coordinating group may be coordinated onthe surface of the quantum dot. It is also possible to use quantum dotsin which such a ligand is already coordinated. Examples of the Lewisbasic coordinating group include an amino group, a carboxy group, amercapto group, a phosphine group, and a phosphine oxide group. Specificexamples thereof include hexylamine, decylamine, hexadecylamine,octadecylamine, oleylamine, myristylamine, laurylamine, oleic acid,mercaptopropionic acid, trioctylphosphine, and trioctylphosphine oxide.Among these, hexadecylamine, trioctylphosphine, and trioctylphosphineoxide are preferable, and trioctylphosphine oxide is particularlypreferable.

Quantum dots in which these ligands are coordinated can be produced by aknown synthesis method. For example, such quantum dots can besynthesized by the method described in C. B. Murray, D. J. Norris, M. G.Bawendi, Journal American Chemical Society, 1993, 115(19), pp. 8706 to8715, or The Journal Physical Chemistry, 101, pp. 9463 to 9475, 1997. Inaddition, commercially available quantum dots in which the ligands arecoordinated can be used without any limitation. For example, Lumidot(manufactured by Sigma-Aldrich Co. LLC.) can be mentioned.

In the present invention, the content of the ligand-coordinated quantumdots is preferably 0.01% to 10% by mass and more preferably 0.05% to 5%by mass with respect to the total mass of the polymerizable compoundcontained in the quantum dot-containing composition to be thefluorescent region. It is desirable to adjust the concentration,depending on the thickness of the phosphor-containing film.

The quantum dots may be added to the quantum dot-containing compositionin the form of particles or in the form of a dispersion liquid dispersedin a solvent. It is preferable to add the quantum dots in the form of adispersion liquid from the viewpoint of suppressing aggregation ofparticles of quantum dots. The solvent used here is not particularlylimited.

(Method for Synthesizing Ligand)

The ligand in the quantum dot-containing composition can be synthesizedby a known synthesis method. For example, the ligand can be synthesizedby the method described in JP2007-277514A.

(Binder Curable Compound in Fluorescent Region)

A compound having a polymerizable group can be widely adopted as thecurable compound. The type of the polymerizable group is notparticularly limited and is preferably a compound having aphotopolymerizable or thermopolymerizable functional group. Further, thepolymerizable group is preferably a (meth)acrylate group, a vinyl group,or an epoxy group, more preferably a (meth)acrylate group, and stillmore preferably an acrylate group. With respect to a polymerizablemonomer having two or more polymerizable groups, the respectivepolymerizable groups may be the same or different.

—(Meth)acrylate-based Compounds—

From the viewpoint of transparency, adhesiveness, or the like of a curedfilm after curing, a (meth)acrylate compound such as a monofunctional orpolyfunctional (meth)acrylate monomer, a polymer or prepolymer thereof,or the like is preferable. In the present invention and the presentspecification, the term “(meth)acrylate” is used to mean at least one orany one of acrylate or methacrylate. The same applies to the term“(meth)acryloyl” and the like.

—Monofunctional Ones—

A monofunctional (meth)acrylate monomer may be, for example, acrylicacid or methacrylic acid, or derivatives thereof, more specifically, amonomer having one polymerizable unsaturated bond ((meth)acryloyl group)of (meth)acrylic acid in the molecule. Specific examples thereof includethe following compounds, but the present embodiment is not limitedthereto.

Examples thereof include alkyl (meth)acrylates having 1 to 30 carbonatoms in the alkyl group, such as methyl (meth)acrylate, n-butyl(meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate,isononyl (meth)acrylate, n-octyl (meth)acrylate, lauryl (meth)acrylate,and stearyl (meth)acrylate; aralkyl (meth)acrylates having 7 to 20carbon atoms in the aralkyl group, such as benzyl (meth)acrylate;alkoxyalkyl (meth)acrylates having 2 to 30 carbon atoms in thealkoxyalkyl group, such as butoxyethyl (meth)acrylate; aminoalkyl(meth)acrylates having 1 to 20 carbon atoms in total in the (monoalkylor dialkyl)aminoalkyl group, such as N,N-dimethylaminoethyl(meth)acrylate; polyalkylene glycol alkyl ether (meth)acrylates having 1to 10 carbon atoms in the alkylene chain and having 1 to 10 carbon atomsin the terminal alkyl ether, such as diethylene glycol ethyl ether(meth)acrylate, triethylene glycol butyl ether (meth)acrylate,tetraethylene glycol monomethyl ether (meth)acrylate, hexaethyleneglycol monomethyl ether (meth)acrylate, octaethylene glycol monomethylether (meth)acrylate, nonaethylene glycol monomethyl ether(meth)acrylate, dipropylene glycol monomethyl ether (meth)acrylate,heptapropylene glycol monomethyl ether (meth)acrylate, and tetraethyleneglycol monoethyl ether (meth)acrylate; polyalkylene glycol aryl ether(meth)acrylates having 1 to 30 carbon atoms in the alkylene chain andhaving 6 to 20 carbon atoms in the terminal aryl ether, such ashexaethylene glycol phenyl ether (meth)acrylate; (meth)acrylates havingan alicyclic structure and having 4 to 30 carbon atoms in total, such ascyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, isobornyl(meth)acrylate, and methylene oxide addition cyclodecatriene(meth)acrylate; fluorinated alkyl (meth)acrylates having 4 to 30 carbonatoms in total, such as heptadecafluorodecyl (meth)acrylate;(meth)acrylates having a hydroxyl group, such as 2-hydroxyethyl(meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethyleneglycol mono(meth)acrylate, hexaethylene glycol mono(meth)acrylate,octapropylene glycol mono(meth)acrylate, and glycerol mono ordi(meth)acrylate; (meth)acrylates having a glycidyl group, such asglycidyl (meth)acrylate; polyethylene glycol mono(meth)acrylates having1 to 30 carbon atoms in the alkylene chain, such as tetraethylene glycolmono(meth)acrylate, hexaethylene glycol mono(meth)acrylate, andoctapropylene glycol mono(meth)acrylate; and (meth)acrylamides such as(meth)acrylamide, N,N-dimethyl (meth)acrylamide, N-isopropyl(meth)acrylamide, 2-hydroxyethyl (meth)acrylamide, andacryloylmorpholine.

The amount of the monofunctional (meth)acrylate monomer to be used ispreferably 10 parts by mass or more and more preferably 10 to 80 partsby mass with respect to 100 parts by mass of the total amount of thecurable compound contained in the coating liquid, from the viewpoint ofadjusting the viscosity of the coating liquid to a preferable range.

—Difunctional Ones—

The polymerizable monomer having two polymerizable groups may be, forexample, a difunctional polymerizable unsaturated monomer having twoethylenically unsaturated bond-containing groups. The difunctionalpolymerizable unsaturated monomer is suitable for allowing a compositionto have a low viscosity. In the present embodiment, preferred is a(meth)acrylate-based compound which is excellent in reactivity and whichhas no problems associated with a remaining catalyst and the like.

In particular, neopentyl glycol di(meth)acrylate, 1,9-nonanedioldi(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropyleneglycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate,hydroxypivalate neopentyl glycol di(meth)acrylate, polyethylene glycoldi(meth)acrylate, dicyclopentenyl(meth)acrylate, dicyclopentenyloxyethyl(meth)acrylate, dicyclopentanyl di(meth)acrylate, or the like issuitably used in the present invention.

The amount of the difunctional (meth)acrylate monomer to be used ispreferably 5 parts by mass or more and more preferably 10 to 80 parts bymass with respect to 100 parts by mass of the total amount of thecurable compound contained in the coating liquid, from the viewpoint ofadjusting the viscosity of the coating liquid to a preferable range.

—Tri- or Higher Functional Ones—

The polymerizable monomer having three or more polymerizable groups maybe, for example, a polyfunctional polymerizable unsaturated monomerhaving three or more ethylenically unsaturated bond-containing groups.Such a polyfunctional polymerizable unsaturated monomer is excellent interms of imparting mechanical strength. In the present embodiment,preferred is a (meth)acrylate-based compound which is excellent inreactivity and which has no problems associated with a remainingcatalyst and the like.

Specifically, epichlorohydrin (ECH)-modified glycerol tri(meth)acrylate,ethylene oxide (EO)-modified glycerol tri(meth)acrylate, propylene oxide(PO)-modified glycerol tri(meth)acrylate, pentaerythritol triacrylate,pentaerythritol tetraacrylate, EO-modified phosphoric acid triacrylate,trimethylolpropane tri(meth)acrylate, caprolactone-modifiedtrimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropanetri(meth)acrylate, PO-modified trimethylolpropane tri(meth)acrylate,tris(acryloxyethyl)isocyanurate, dipentaerythritol hexa(meth)acrylate,dipentaerythritol penta(meth)acrylate, caprolactone-modifieddipentaerythritol hexa(meth)acrylate, dipentaerythritolhydroxypenta(meth)acrylate, alkyl-modified dipentaerythritolpenta(meth)acrylate, dipentaerythritol poly(meth)acrylate,alkyl-modified dipentaerythritol tri(meth)acrylate, ditrimethylolpropanetetra(meth)acrylate, pentaerythritolethoxy tetra(meth)acrylate,pentaerythritol tetra(meth)acrylate, or the like is suitable.

Among them, EO-modified glycerol tri(meth)acrylate, PO-modified glyceroltri(meth)acrylate, trimethylolpropane tri(meth)acrylate, EO-modifiedtrimethylolpropane tri(meth)acrylate, PO-modified trimethylolpropanetri(meth)acrylate, dipentaerythritol hexa(meth)acrylate,dipentaerythritol penta(meth)acrylate, pentaerythritolethoxytetra(meth)acrylate, or pentaerythritol tetra(meth)acrylate is suitablyused in the present invention.

The amount of the polyfunctional (meth)acrylate monomer to be used ispreferably 5 parts by mass or more from the viewpoint of the coatingfilm hardness of the fluorescent-containing layer after curing, andpreferably 95 parts by mass or less from the viewpoint of suppressinggelation of the coating liquid, with respect to 100 parts by mass of thetotal amount of the curable compound contained in the coating liquid.

From the viewpoint of further improving the heat resistance of thefluorescent region (binder), the (meth)acrylate monomer is preferably analicyclic acrylate. Examples of such a monofunctional (meth)acrylatemonomer include dicyclopentenyl (meth)acrylate, dicyclopentanyl(meth)acrylate, and dicyclopentenyloxyethyl (meth)acrylate. Examples ofthe difunctional (meth)acrylate monomer include tricyclodecanedimethanoldi(meth)acrylate.

The total amount of the polymerizable compound in the curablecomposition forming a binder is preferably 70 to 99 parts by mass andmore preferably 85 to 97 parts by mass with respect to 100 parts by massof the curable composition, from the viewpoint of handleability andcurability of the composition.

—Epoxy-Based Compounds and Others—

The polymerizable monomer used in the present embodiment may be, forexample, a compound having a cyclic group such as a ring-openingpolymerizable cyclic ether group such as an epoxy group or an oxetanylgroup. Such a compound may be more preferably, for example, a compoundhaving a compound (epoxy compound) having an epoxy group. Use of thecompound having an epoxy group or an oxetanyl group in combination withthe (meth)acrylate-based compound tends to improve adhesiveness to thebarrier layer.

Examples of the compound having an epoxy group include polyglycidylesters of polybasic acids, polyglycidyl ethers of polyhydric alcohols,polyglycidyl ethers of polyoxyalkylene glycols, polyglycidyl esters ofaromatic polyols, hydrogenated compounds of polyglycidyl ethers ofaromatic polyols, urethane polyepoxy compounds, and epoxidizedpolybutadienes. These compounds may be used alone or in combination oftwo or more thereof.

Examples of other compounds having an epoxy group, which may bepreferably used, include aliphatic cyclic epoxy compounds, bisphenol Adiglycidyl ethers, bisphenol F diglycidyl ethers, bisphenol S diglycidylethers, brominated bisphenol A diglycidyl ethers, brominated bisphenol Fdiglycidyl ethers, brominated bisphenol S diglycidyl ethers,hydrogenated bisphenol A diglycidyl ethers, hydrogenated bisphenol Fdiglycidyl ethers, hydrogenated bisphenol S diglycidyl ethers,1,4-butanediol diglycidyl ethers, 1,6-hexanediol diglycidyl ethers,glycerin triglycidyl ethers, trimethylolpropane triglycidyl ethers,polyethylene glycol diglycidyl ethers, and polypropylene glycoldiglycidyl ethers; polyglycidyl ethers of polyether polyols, obtained byadding one or two or more alkylene oxides to an aliphatic polyhydricalcohol such as ethylene glycol, propylene glycol, or glycerin;diglycidyl esters of aliphatic long chain dibasic acids; monoglycidylethers of aliphatic higher alcohols; monoglycidyl ethers of polyetheralcohols, obtained by adding an alkylene oxide to phenol, cresol, butylphenol, or these compounds; and glycidyl esters of higher fatty acids.

Among these components, aliphatic cyclic epoxy compounds, bisphenol Adiglycidyl ethers, bisphenol F diglycidyl ethers, hydrogenated bisphenolA diglycidyl ethers, hydrogenated bisphenol F diglycidyl ethers,1,4-butanediol diglycidyl ethers, 1,6-hexanediol diglycidyl ethers,glycerin triglycidyl ethers, trimethylolpropane triglycidyl ethers,neopentyl glycol diglycidyl ethers, polyethylene glycol diglycidylethers, and polypropylene glycol diglycidyl ethers are preferable.

Examples of commercially available products which can be suitably usedas the compound having an epoxy group or an oxetanyl group includeUVR-6216 (manufactured by Union Carbide Corporation), glycidol, AOEX24,CYCLOMER A200, CELLOXIDE 2021P and CELLOXIDE 8000 (all manufactured byDaicel Corporation), 4-vinylcyclohexene dioxide manufactured by SigmaAldrich, Inc., EPIKOTE 828, EPIKOTE 812, EPIKOTE 1031, EPIKOTE 872 andEPIKOTE CT508 (all manufactured by Yuka Shell Epoxy K.K.), and KRM-2400,KRM-2410, KRM-2408, KRM-2490, KRM-2720 and KRM-2750 (all manufactured byAsahi Denka Kogyo K.K.). These compounds may be used alone or incombination of two or more thereof.

Although there are no particular restrictions on the production methodof such a compound having an epoxy group or an oxetanyl group, thecompound can be synthesized with reference to, for example, Literaturessuch as Fourth Edition Experimental Chemistry Course 20 OrganicSynthesis II, p. 213˜, 1992, published by Maruzen KK; Ed. by AlfredHasfner, The chemistry of heterocyclic compounds-Small Ring Heterocyclespart 3 Oxiranes, John & Wiley and Sons, An Interscience Publication, NewYork, 1985, Yoshimura, Adhesion, Vol. 29, No. 12, 32, 1985, Yoshimura,Adhesion, Vol. 30, No. 5, 42, 1986, Yoshimura, Adhesion, Vol. 30, No. 7,42, 1986, JP1999-100378A (JP-H11-100378A), JP2906245B, and JP2926262B.

A vinyl ether compound may be used as the curable compound used in thepresent embodiment.

As the vinyl ether compound, a known vinyl ether compound can beappropriately selected, and, for example, the compound described inparagraph [0057] of JP2009-073078A may be preferably adopted.

Such a vinyl ether compound can be synthesized by, for example, themethod described in Stephen. C. Lapin, Polymers Paint Colour Journal.179 (4237), 321 (1988), namely, by a reaction of a polyhydric alcohol ora polyhydric phenol with acetylene, or a reaction of a polyhydricalcohol or a polyhydric phenol with a halogenated alkyl vinyl ether, andsuch method and reactions may be used alone or in combination of two ormore thereof.

For the coating liquid of the present embodiment, a silsesquioxanecompound having a reactive group described in JP2009-073078A can also beused from the viewpoint of a decrease in viscosity and an increase inhardness.

Among the foregoing curable compounds, a (meth)acrylate compound ispreferable from the viewpoint of composition viscosity andphotocurability, and acrylate is more preferable. In the presentinvention, a polyfunctional polymerizable compound having two or morepolymerizable functional groups is preferable. In the present invention,particularly, the compounding ratio of the monofunctional (meth)acrylatecompound to the polyfunctional (meth)acrylate compound is preferably80/20 to 0/100, more preferably 70/30 to 0/100, and still morepreferably 40/60 to 0/100 in terms of weight ratio. By selecting anappropriate ratio, it is possible to provide sufficient curability andmake the composition low in viscosity.

The ratio of the difunctional (meth)acrylate to the tri- or higherfunctional (meth)acrylate in the polyfunctional (meth)acrylate compoundis preferably 100/0 to 20/80, more preferably 100/0 to 50/50, and stillmore preferably 100/0 to 70/30 in terms of mass ratio. Since the tri- orhigher functional (meth)acrylate has a higher viscosity than thedifunctional (meth)acrylate, a larger amount of the difunctional(meth)acrylate is preferable because the viscosity of the curablecompound for a resin layer having impermeability to oxygen in thepresent invention can be lowered.

From the viewpoint of enhancing the impermeability to oxygen, it ispreferable to include a compound containing a substituent having anaromatic structure and/or an alicyclic hydrocarbon structure as thepolymerizable compound. The polymerizable compound having an aromaticstructure and/or an alicyclic hydrocarbon structure is more preferablycontained in an amount of 50% by mass or more and still more preferably80% by mass or more. The polymerizable compound having an aromaticstructure is preferably a (meth)acrylate compound having an aromaticstructure. As the (meth)acrylate compound having an aromatic structure,a monofunctional (meth)acrylate compound having a naphthalene structure,such as 1- or 2-naphthyl (meth)acrylate, 1- or 2-naphthylmethyl(meth)acrylate, or 1- or 2-naphthylethyl (meth)acrylate, amonofunctional acrylate having a substituent on the aromatic ring, suchas benzyl acrylate, and a difunctional acrylate such as catecholdiacrylate or xylylene glycol diacrylate are particularly preferable. Asthe polymerizable compound having an alicyclic hydrocarbon structure,isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate,dicyclopentanyloxyethyl (meth)acrylate, dicyclopentenyl (meth)acrylate,adamantyl (meth)acrylate, tricyclodecanyl (meth)acrylate,tetracyclododecanyl (meth)acrylate, and the like are preferable.

In addition, in the case where (meth)acrylate is used as thepolymerizable compound, acrylate is preferable to methacrylate from theviewpoint of excellent curability.

(Thixotropic Agent)

The curable compound may contain a thixotropic agent.

The thixotropic agent is an inorganic compound or an organic compound.

—Inorganic Compound—

One preferred aspect of the thixotropic agent is a thixotropic agent ofan inorganic compound, and, for example, a needle-like compound, achain-like compound, a flattened compound, or a layered compound can bepreferably used. Among them, a layered compound is preferable.

The layered compound is not particularly limited and examples thereofinclude talc, mica, feldspar, kaolinite (kaolin clay), pyrophyllite(pyrophyllite clay), sericite (silk mica), bentonite,smectite-vermiculites (montmorillonite, beidellite, non-tronite,saponite, and the like), organic bentonite, and organic smectite.

These compounds may be used alone or in combination of two or morethereof. Examples of commercially available layered compounds include,as inorganic compounds, CROWN CLAY, BURGESS CLAY #60, BURGESS CLAY KFand OPTIWHITE (all manufactured by Shiraishi Kogyo Kaisha Ltd.), KAOLINJP-100, NN KAOLIN CLAY, ST KAOLIN CLAY AND HARDSEAL (all manufactured byTsuchiya Kaolin Ind., Ltd.), ASP-072, SATINTONPLUS, TRANSLINK 37 andHYDROUSDELAMI NCD (all manufactured by Angel Hard Corporation), SYKAOLIN, OS CLAY, HA CLAY and MC HARD CLAY (all manufactured by MaruoCalcium Co., Ltd.), RUCENTITE SWN, RUCENTITE SAN, RUCENTITE STN,RUCENTITE SEN and RUCENTITE SPN (all manufactured by Co-op Chemical Co.,Ltd.), SUMECTON (manufactured by Kunimine Industries Co., Ltd.), BENGEL,BENGEL FW, ESBEN, ESBEN 74, ORGANITE and ORGANITE T (all manufactured byHojun Co., Ltd.), HODAKA JIRUSHI, ORBEN, 250M, BENTONE 34 and BENTONE 38(all manufactured by Wilbur-Ellis Company), and LAPONITE, LAPONITE RDand LAPONITE RDS (all manufactured by Nippon Silica Industrial Co.,Ltd.). These compounds may also be dispersed in a solvent.

The thixotropic agent to be added to the coating liquid is, amonglayered inorganic compounds, a silicate compound represented byxM(I)₂O.ySiO₂ (also including a compound corresponding to M(II)O orM(III)₂O₃ having an oxidation number of 2 or 3; x and y represent apositive number), and a further preferred compound is a swellablelayered clay mineral such as hectorite, bentonite, smectite, orvermiculite.

Particularly preferably, a layered (clay) compound modified with anorganic cation (a compound in which an interlayer cation such as sodiumin a silicate compound is exchanged with an organic cation compound) canbe suitably used, and examples thereof include compounds in which asodium ion in sodium magnesium silicate (hectorite) is exchanged with anammonium ion which will be described below.

Examples of the ammonium ion include a monoalkyltrimethylammonium ion, adialkyldimethylammonium ion and a trialkylmethylammonium ion, eachhaving an alkyl chain having 6 to 18 carbon atoms, adipolyoxyethylene-palm oil-alkylmethylammonium ion and abis(2-hydroxyethyl)-palm oil-alkylmethylammonium ion, each having 4 to18 oxyethylene chains, and a polyoxypropylene methyldiethylammonium ionhaving 4 to 25 oxopropylene chains. These ammonium ions may be usedalone or in combination of two or more thereof.

The method for producing an organic cation-modified silicate mineral inwhich a sodium ion of sodium magnesium silicate is exchanged with anammonium ion is as follows: sodium magnesium silicate is dispersed inwater and sufficiently stirred, and thereafter allowed to stand for 16hours or more to prepare a 4% by mass dispersion liquid; while thisdispersion liquid is stirred, a desired ammonium salt is added in anamount of 30% by mass to 200% by mass relative to sodium magnesiumsilicate; after the addition, cation exchange takes place, and hectoritecontaining an ammonium salt between the layers becomes insoluble inwater and precipitates, and therefore the precipitate is collected byfiltration and dried. In the preparation, heating may also be carriedout for the purpose of accelerating the dispersion.

Commercially available products of the alkylammonium-modified silicatemineral include RUCENTITE SAN, RUCENTITE SAN-316, RUCENTITE STN,RUCENTITE SEN, and RUCENTITE SPN (all manufactured by Co-op ChemicalCo., Ltd.), which may be used alone or in combination of two or morethereof.

In the present embodiment, silica, alumina, silicon nitride, titaniumdioxide, calcium carbonate, zinc oxide, or the like can be used as thethixotropic agent of an inorganic compound. These compounds may also besubjected to a treatment to adjust hydrophilicity or hydrophobicity onthe surface, as necessary.

—Organic Compound—For the thixotropic agent, a thixotropic agent of anorganic compound can be used. Examples of the thixotropic agent of anorganic compound include an oxidized polyolefin and a modified urea.

The above-mentioned oxidized polyolefin may be independently preparedin-house or may be a commercially available product. Examples ofcommercially available products include DISPARLON 4200-20 (trade name,manufactured by Kusumoto Chemicals, Ltd.) and FLOWNON SA300 (trade name,manufactured by Kyoeisha Chemical Co., Ltd.).

The above-mentioned modified urea is a reaction product of an isocyanatemonomer or an adduct thereof with an organic amine. The above-mentionedmodified urea may be independently prepared in-house or may be acommercially available product. The commercially available product maybe, for example, BYK 410 (manufactured by BYK-Chemie GmbH).

—Content—

The content of the thixotropic agent in the coating liquid is preferably0.15 to 20 parts by mass, more preferably 0.2 to 10 parts by mass, andparticularly preferably 0.2 to 8 parts by mass, with respect to 100parts by mass of the curable compound. In particular, in the case of thethixotropic agent of an inorganic compound, the content of 20 parts bymass or less with respect to 100 parts by mass of the curable compoundtends to improve brittleness.

(Polymerization Initiator)

The coating liquid may contain a known polymerization initiator as apolymerization initiator. With respect to the polymerization initiator,for example, reference can be made to paragraph [0037] ofJP2013-043382A. The polymerization initiator is preferably in an amountof 0.1% by mol or more and more preferably 0.5% to 2% by mol based onthe total amount of the curable compound contained in the coatingliquid. In addition, the polymerization initiator is preferablycontained in an amount of 0.1% by mass to 10% by mass and morepreferably 0.2% by mass to 8% by mass, as the percentage by mass in thetotal curable composition excluding the volatile organic solvent.

—Photopolymerization Initiator—

The curable compound forming the resin layer 38 having impermeability tooxygen preferably contains a photopolymerization initiator. Anyphotopolymerization initiator may be used as long as it is a compoundcapable of generating an active species that polymerizes thepolymerizable compound upon irradiation with light. Examples of thephotopolymerization initiator include a cationic polymerizationinitiator and a radical polymerization initiator, among which a radicalpolymerization initiator is preferable. Further, in the presentinvention, a plurality of photopolymerization initiators may be used incombination.

The content of the photopolymerization initiator is, for example, 0.01%to 15% by mass, preferably 0.1% to 12% by mass, and more preferably 0.2%to 7% by mass, in the total composition excluding the solvent. In thecase where two or more photopolymerization initiators are used, thetotal content thereof falls within the above range.

In the case where the content of the photopolymerization initiator is0.01% by mass or more, sensitivity (fast curability) and coating filmhardness tend to improve, which is preferable. On the other hand, in thecase where the content of the photopolymerization initiator is 15% bymass or less, light transmittance, colorability, handleability, and thelike tend to improve, which is preferable. In a system including a dyeand/or a pigment, they may act as a radical trapping agent and affectphotopolymerizability and sensitivity. In consideration of this point,in these applications, the addition amount of the photopolymerizationinitiator is optimized. On the other hand, in the composition used inthe present invention, the dye and/or pigment is not an essentialcomponent, and the optimum range of the photopolymerization initiatormay be different from that in the field of a curable composition forliquid crystal display color filter, or the like.

As the radical photopolymerization initiator, for example, acommercially available initiator can be used. The examples thereofinclude those described, for example, in paragraph [0091] ofJP2008-105414A, which are preferably used. Among them, anacetophenone-based compound, an acylphosphine oxide-based compound, andan oxime ester-based compound are preferable from the viewpoint ofcuring sensitivity and absorption properties.

The acetophenone-based compound may be preferably, for example, ahydroxyacetophenone-based compound, a dialkoxyacetophenone-basedcompound, and an aminoacetophenone-based compound. Thehydroxyacetophenone-based compound may be preferably, for example,Irgacure (registered trademark) 2959(1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one,Irgacure (registered trademark) 184 (1-hydroxycyclohexyl phenylketone),Irgacure (registered trademark) 500 (1-hydroxycyclohexyl phenylketone,benzophenone), and Darocur (registered trademark) 1173(2-hydroxy-2-methyl-1-phenyl-1-propan-1-one), all of which arecommercially available from BASF Corporation. Thedialkoxyacetophenone-based compound may be preferably, for example,Irgacure (registered trademark) 651(2,2-dimethoxy-1,2-diphenylethan-1-one) which is commercially availablefrom BASF Corporation.

The aminoacetophenone-based compound may be preferably, for example,Irgacure (registered trademark) 369(2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone-1), Irgacure(registered trademark) 379 (EG)(2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)butan-1-one, and Irgacure (registered trademark) 907(2-methyl-1-[4-methylthiophenyl]-2-morpholinopropan-1-one), all of whichare commercially available from BASF Corporation.

The acylphosphine oxide-based compound may be preferably, for example,Irgacure (registered trademark) 819(bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide), and Irgacure(registered trademark) 1800(bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide), allof which are commercially available from BASF Corporation, and LucirinTPO (2,4,6-trimethylbenzoyldiphenylphosphine oxide) and Lucirin TPO-L(2,4,6-trimethylbenzoylphenylethoxyphosphine oxide), both of which arecommercially available from BASF Corporation.

The oxime ester-based compound may be preferably, for example, Irgacure(registered trademark) OXE01 (1,2-octanedione,1-[4-(phenylthio)phenyl]-2-(O-benzoyloxime)), Irgacure (registeredtrademark) OXE02 (ethanone,1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, and1-(O-acetyloxime)), all of which are commercially available from BASFCorporation.

The cationic photopolymerization initiator is preferably a sulfoniumsalt compound, an iodonium salt compound, an oxime sulfonate compound,or the like, and examples thereof include4-methylphenyl[4-(1-methylethyl)phenyliodoniumtetrakis(pentafluorophenyl)borate (PI 2074 manufactured by Rhodia),4-methylphenyl[4-(2-methylpropyl)phenyliodonium hexafluorophosphate(IRGACURE 250 manufactured by BASF Corporation), and IRGACURE PAG103,108, 121, and 203 (all manufactured by BASF Corporation).

The photopolymerization initiator needs to be selected appropriatelywith respect to the wavelength of the light source to be used, but it ispreferable that the photopolymerization initiator does not generate gasduring mold pressurization/exposure. In the case where gas is generated,the mold is contaminated, so it is necessary to frequently clean themold, or the photocurable composition is deformed in the mold, whichcontributes to problems such as deterioration of transfer patternaccuracy.

(Polymer)

The curable composition forming the resin layer 38 having impermeabilityto oxygen may contain a polymer. Examples of the polymer includepoly(meth)acrylate, poly(meth)acrylamide, polyester, polyurethane,polyurea, polyamide, polyether, and polystyrene.

(Other Additives)

The coating liquid for forming a fluorescent region may contain aviscosity adjuster, a silane coupling agent, a surfactant, anantioxidant, an oxygen getter, a polymerization inhibitor, an inorganicparticle, and the like.

—Viscosity Adjuster—

The coating liquid for forming a fluorescent region may contain aviscosity adjuster, if necessary. Addition of a viscosity adjuster makesit possible to adjust to the desired viscosity. The viscosity adjusteris preferably a filler having a particle diameter of 5 nm to 300 nm. Inaddition, the viscosity adjuster may be a thixotropic agent. In thepresent invention and the present specification, the term “thixotropy”refers to a property of decreasing the viscosity with increasing shearrate in a liquid composition, and the term “thixotropic agent” refers toa material having a function of imparting thixotropy to a composition byincorporation thereof into a liquid composition. Specific examples ofthe thixotropic agent include fumed silica, alumina, silicon nitride,titanium dioxide, calcium carbonate, zinc oxide, talc, mica, feldspar,kaolinite (kaolin clay), pyrophyllite (pyrophyllite clay), sericite(silk mica), bentonite, smectite-vermiculites (montmorillonite,beidellite, nontronite, saponite, and the like), organic bentonite, andorganic smectite.

—Silane Coupling Agent—

The phosphor-containing layer formed from the coating liquid containinga silane coupling agent can exhibit excellent durability due to havingstrong adhesiveness to an adjacent layer due to the silane couplingagent. In addition, the phosphor-containing layer formed from thecoating liquid containing a silane coupling agent is also preferable informing the relationship of adhesion force A between support film andbarrier layer<adhesion force B between phosphor-containing layer andbarrier layer, under adhesion force conditions. This is mainly due tothe fact that the silane coupling agent contained in thephosphor-containing layer forms a covalent bond with the surface of theadjacent layer or the constituent component of the phosphor-containinglayer by hydrolysis reaction or condensation reaction. In the case wherethe silane coupling agent has a reactive functional group such as aradical polymerizable group, the formation of a crosslinking structurewith a monomer component constituting the phosphor-containing layer canalso contribute to an improvement in adhesiveness to the layer adjacentto the phosphor-containing layer.

For the silane coupling agent, a known silane coupling agent can be usedwithout any limitation. From the viewpoint of adhesiveness, a preferredsilane coupling agent may be, for example, a silane coupling agentrepresented by General Formula (1) described in JP2013-043382A.

(In General Formula (1), R₁ to R₆ are each independently a substitutedor unsubstituted alkyl group or aryl group, provided that at least oneof R₁, . . . , or R₆ is a substituent containing a radical polymerizablecarbon-carbon double bond.)

R₁ to R₆ are preferably an unsubstituted alkyl group or an unsubstitutedaryl group, except for a case where R₁ to R₆ are a substituentcontaining a radical polymerizable carbon-carbon double bond. The alkylgroup is preferably an alkyl group having 1 to 6 carbon atoms and morepreferably a methyl group. The aryl group is preferably a phenyl group.R₁ to R₆ are each particularly preferably a methyl group.

It is preferable that at least one of R₁, . . . , or R₆ has asubstituent containing a radical polymerizable carbon-carbon doublebond, and two of R₁ to R₆ are a substituent containing a radicalpolymerizable carbon-carbon double bond. Further, it is particularlypreferable that among R₁ to R₃, the number of those having a substituentcontaining a radical polymerizable carbon-carbon double bond is 1, andamong R₄ to R₆, the number of those having a substituent containing aradical polymerizable carbon-carbon double bond is 1.

In the case where the silane coupling agent represented by GeneralFormula (1) has two or more substituents containing a radicalpolymerizable carbon-carbon double bond, the respective substituents maybe the same or different, and are preferably the same.

It is preferable that the substituent containing a radical polymerizablecarbon-carbon double bond is represented by —X—Y where X is a singlebond, an alkylene group having 1 to 6 carbon atoms, or an arylene group,preferably a single bond, a methylene group, an ethylene group, apropylene group, or a phenylene group; and Y is a radical polymerizablecarbon-carbon double bond group, preferably an acryloyloxy group, amethacryloyloxy group, an acryloylamino group, a methacryloylaminogroup, a vinyl group, a propenyl group, a vinyloxy group, or avinylsulfonyl group, and more preferably a (meth)acryloyloxy group.

R₁ to R₆ may also have a substituent other than the substituentcontaining a radical polymerizable carbon-carbon double bond. Examplesof such a substituent include alkyl groups (for example, a methyl group,an ethyl group, an isopropyl group, a tert-butyl group, a n-octyl group,an n-decyl group, an n-hexadecyl group, a cyclopropyl group, acyclopentyl group, and a cyclohexyl group), aryl groups (for example, aphenyl group and a naphthyl group), halogen atoms (for example,fluorine, chlorine, bromine, and iodine), acyl groups (for example, anacetyl group, a benzoyl group, a formyl group, and a pivaloyl group),acyloxy groups (for example, an acetoxy group, an acryloyloxy group, anda methacryloyloxy group), alkoxycarbonyl groups (for example, amethoxycarbonyl group and an ethoxycarbonyl group), aryloxycarbonylgroups (for example, a phenyloxycarbonyl group), and sulfonyl groups(for example, a methanesulfonyl group and a benzenesulfonyl group).

The silane coupling agent is contained in the coating liquid in therange of preferably 1% to 30% by mass, more preferably 3% to 30% bymass, and still more preferably 5% to 25% by mass, from the viewpoint offurther improving the adhesiveness to the adjacent layer.

—Surfactant—

The coating liquid for forming a fluorescent region may contain at leastone surfactant containing fluorine atoms in an amount of 20% by mass ormore.

The surfactant preferably contains 25% by mass or more of fluorine atomsand more preferably 28% by mass or more of fluorine atoms. The upperlimit value of the fluorine atom content is not specifically defined,but it is, for example, 80% by mass or less and preferably 70% by massor less.

The surfactant used in the present invention is preferably a compoundhaving an alkyl group having a fluorine atom, a cycloalkyl group havinga fluorine atom, or an aryl group having a fluorine atom.

The alkyl group containing a fluorine atom is a linear or branched alkylgroup in which at least one hydrogen atom is substituted with a fluorineatom. The alkyl group preferably has 1 to 10 carbon atoms and morepreferably 1 to 4 carbon atoms. The alkyl group containing a fluorineatom may further have a substituent other than a fluorine atom.

The cycloalkyl group containing a fluorine atom is a monocyclic orpolycyclic cycloalkyl group in which at least one hydrogen atom issubstituted with a fluorine atom. The cycloalkyl group containing afluorine atom may further have a substituent other than a fluorine atom.

The aryl group containing a fluorine atom is an aryl group in which atleast one hydrogen atom is substituted with a fluorine atom. Examples ofthe aryl group include a phenyl group and a naphthyl group. The arylgroup containing a fluorine atom may further have a substituent otherthan a fluorine atom.

By having such a structure, it is considered that the surface unevendistribution ability becomes satisfactory, and partial compatibilitywith the polymer occurs and phase separation is suppressed.

The molecular weight of the surfactant is preferably 300 to 10,000 andmore preferably 500 to 5,000.

The content of the surfactant is, for example, 0.01% to 10% by mass,preferably 0.1% to 7% by mass, and more preferably 0.5% to 4% by mass inthe total composition excluding the solvent. In the case where two ormore surfactants are used, the total content thereof falls within theabove range.

Examples of the surfactant include FLUORAD FC-430 and FC-431 (tradenames, manufactured by Sumitomo 3M Ltd.), SURFLON S-382 (trade name,manufactured by Asahi Glass Co., Ltd.), EFTOP “EF-122A, 122B, 122C,EF-121, EF-126, EF-127, and MF-100” (manufactured by Tohkem ProductsCorporation), PF-636, PF-6320, PF-656 and PF-6520 (trade names, allmanufactured by OMNOVA Solutions, Inc.), FTERGENT FT250, FT251 and DFX18(trade names, all manufactured by NEOS Co., Ltd.), UNIDYNE DS-401,DS-403 and DS-451 (trade names, all manufactured by Daikin IndustriesLtd.), MEGAFACE 171, 172, 173, 178K and 178A (trade names, allmanufactured by DIC Corporation), X-70-090, X-70-091, X-70-092 andX-70-093 (trade names, all manufactured by Shin-Etsu Chemical Co.,Ltd.), and MEGAFACE R-08 and XRB-4 (trade names, all manufactured by DICCorporation).

—Antioxidant—

The curable compound forming the resin layer 38 having impermeability tooxygen preferably contains a known antioxidant. The antioxidant is forsuppressing color fading by heat or photo-irradiation, and forsuppressing color fading by various oxidizing gases such as ozone,active oxygen NOx, and SOx (X is an integer). Especially in the presentinvention, addition of the antioxidant brings about advantages that thecured film is prevented from being colored and the film thickness isprevented from being reduced through decomposition.

Further, two or more antioxidants may be used as the antioxidant.

The content of the antioxidant in the curable compound forming the resinlayer 38 having impermeability to oxygen is preferably 0.2% by mass ormore, more preferably 1% by mass or more, and still more preferably 2%by mass or more with respect to the total mass of the curable compound.On the other hand, the antioxidant may be altered due to the interactionwith oxygen. The altered antioxidant may induce decomposition of thequantum dot-containing polymerizable composition, resulting in loweringof adhesiveness, brittleness deterioration, and lowering of quantum dotluminous efficiency. From the viewpoint of preventing thesedeteriorations, the content of the antioxidant is preferably 20% by massor less, more preferably 15% by mass or less, and still more preferably10% by mass or less.

The antioxidant is preferably at least one of a radical inhibitor, ametal deactivator, a singlet oxygen scavenger, a superoxide scavenger,or a hydroxy radical scavenger. Examples of the antioxidant include aphenol-based antioxidant, a hindered amine-based antioxidant, aquinone-based antioxidant, a phosphorus-based antioxidant, and athiol-based antioxidant.

Examples of the phenol-based antioxidant include2,6-di-tert-butyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, distearyl(3,5-di-tert-butyl-4-hydroxybenzyl)phosphonate,1,6-hexamethylenebis[(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acidamide], 4,4′-thiobis(6-tert-butyl-m-cresol),2,2′-methylenebis(4-methyl-6-tert-butylphenol),2,2′-methylenebis(4-ethyl-6-tert-butylphenol),4,4′-butylidenebis(6-tert-butyl-m-cresol),2,2′-ethylidenebis(4,6-di-tert-butylphenol),2,2′-ethylidenebis(4-sec-butyl-6-tert-butylphenol),1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyebutane,1,3,5-tris(2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl)isocy anurate,1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate,1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene,2-tert-butyl-4-methyl-6-(2-acryloyloxy-3-tert-butyl-5-methylbenzyl)phenol,stearyl(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acidmethyl]methane ((ADEKASTAB AO-60, manufactured by ADEKA Corporation)),thiodiethylene glycolbis[(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,6-hexamethylenebis[(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], bis[3,3-bis(4-hydroxy-3-tert-butylphenyebutyl acid]glycol ester,bis[2-tert-butyl-4-methyl-6-(2-hydroxy-3-tert-butyl-5-methylbenzyl)phenyl]terephthalate,1,3,5-tris[(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxyethyl]isocyanurate,3,9-bis[1,1-dimethyl-2-{(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane, and triethylene glycolbis[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate].

Examples of the phosphorus-based antioxidant include trisnonylphenylphosphite,tris[2-tert-butyl-4-(3-tert-butyl-4-hydroxy-5-methylphenylthio)-5-methylphenyl]phosphite,tridecyl phosphite, octyldiphenyl phosphite, di(decyl)monophenylphosphite, di(tridecyl)pentaerythritol diphosphite,di(nonylphenyl)pentaerythritol diphosphite,bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite,bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite,bis(2,4,6-tri-tert-butylphenyl)pentaerythritol diphosphite,bis(2,4-dicumylphenyl)pentaerythritol diphosphite,tetra(tridecyl)isopropylidenediphenol diphosphite,tetra(tridecyl)-4,4′-n-butylidenebis(2-tert-butyl-5-methylphenol)diphosphite,hexa(tridecyl)-1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butanetriphosphite, tetrakis (2,4-di-tert-butylphenyl)biphenylenediphosphonite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide,2,2′-methylene-bis(4,6-tert-butylphenyl)-2-ethylhexyl phosphite,2,2′-methylene-bis(4,6-tert-butylphenyl)-octadecyl phosphite,2,2′-ethylidene-bis(4,6-di-tert-butylphenyl)fluorophosphite,tris(2-[(2,4,8,10-tetrakis-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl)oxy]ethyeamine, and phosphites of 2-ethyl-2-butylpropylene glycol and2,4,6-tri-tert-butylphenol. The amount of these phosphorus-basedantioxidants added is preferably 0.001 to 10 parts by mass andparticularly preferably 0.05 to 5 parts by mass, with respect to 100parts by mass of the polyolefin-based resin.

Examples of the thiol-based antioxidant include dialkylthiodipropionates such as dilauryl thiodipropionate, dimyristylthiodipropionate, and distearyl thiodipropionate; and pentaerythritoltetra(β-alkyl mercaptopropionic acid) esters.

The hindered amine-based antioxidant is also referred to as a hinderedamine light stabilizer (HALS), and has a structure in which all hydrogenatoms on carbons at 2- and 6-positions of piperidine are substitutedwith methyl groups, preferably a group represented by Formula 1. InFormula 1, X represents a hydrogen atom or an alkyl group. Among thegroups represented by Formula 1, HALS having a2,2,6,6-tetramethyl-4-piperidyl group in which X is a hydrogen atom, ora 1,2,2,6,6-pentamethyl-4-piperidyl group in which X is a methyl groupis particularly preferably adopted. A number of HALS having a structurein which a group represented by Formula 1 is bonded to a —COO— group,that is, a group represented by Formula 2 are commercially available,but these can be preferably used.

Specific examples of HALS that can be preferably used in the presentinvention include those represented by the following formulae. Here, the2,2,6,6-tetramethyl-4-piperidyl group is represented by R and the1,2,2,6,6-pentamethyl-4-piperidyl group is represented by R′.

ROC(═O)(CH₂)₈C(═O)OR, ROC(═O)C(CH₃)═CH₂, R′OC(═O)C(CH₃)═CH₂,CH₂(COOR)CH(COOR)CH(COOR)CH₂COOR, CH₂(COOR′)CH(COOR′)CH(COOR′)CH₂COOR′,a compound represented by Formula 3, and the like.

Specific examples of HALS include hindered amine compounds such as2,2,6,6-tetramethyl-4-piperidylstearate,1,2,2,6,6-pentamethyl-4-piperidylstearate,2,2,6,6-tetramethyl-4-piperidylbenzoate,bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate,bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate,bis(1-octoxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate,tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate,tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate,bis(2,2,6,6-tetramethyl-4-piperidyl)-di(tridecyl)-1,2,3,4-butanetetracarboxylate,bis(1,2,2,6,6-pentamethyl-4-piperidyl)-di(tridecyl)-1,2,3,4-butanetetracarboxylate,bis(1,2,2,4,4-pentamethyl-4-piperidyl)-2-butyl-2-(3,5-di-tert-butyl-4-hydroxybenzyl)malonate,1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol/diethyl succinatepolycondensate,1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane/2,4-dichloro-6-morpholino-s-triazinepolycondensate,1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane/2,4-dichloro-6-tert-octylamino-s-triazinepolycondensate,1,5,8,12-tetrakis[2,4-bis(N-butyl-N-(2,2,6,6-tetramethyl-4-piperidyl)amino)-s-triazin-6-yl]-1,5,8,12-tetraazadodecane,1,5,8,12-tetrakis[2,4-bis(N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyeamino)-s-triazin-6-yl]-1,5,8,12-tetraazadodecane,1,6,11-tris[2,4-bis(N-butyl-N-(2,2,6,6-tetramethyl-4-piperidyl)amino)-s-triazin-6-yl]aminoundecane,and1,6,11-tris[2,4-bis(N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyeamino)-s-triazin-6-yl]aminoundecane.

Specific products of HALS include, but are not limited to, TINUVIN 123,TINUVIN 144, TINUVIN 765, TINUVIN 770, TINUVIN 622, CHIMASSORB 944, andCHIMASSORB 119 (all of which are trade names of Ciba Specialty ChemicalsInc.), ADEKASTAB LA 52, ADEKASTAB LA 57, ADEKASTAB LA-62, ADEKASTABLA-67, ADEKASTAB LA 82, ADEKASTAB LA 87, and ADEKASTAB LX 335 (all ofwhich are trade names of Asahi Denka Kogyo KK).

Among the HALS, those having a relatively small molecular weight arepreferable because of easy diffusion from the resin layer to thefluorescent region. Preferred HALS in this viewpoint are compoundsrepresented by ROC(═O)(CH₂)₈C(═O)OR, R′OC(═O)C(CH₃)═CH₂, and the like.

Among the above-mentioned antioxidants, at least one of a hinderedphenol compound, a hindered amine compound, a quinone compound, ahydroquinone compound, a tocopherol compound, an aspartic acid compound,or a thiol compound is more preferable, and at least one of a citricacid compound, an ascorbic acid compound, or a tocopherol compound isstill more preferable. Although these compounds are not particularlylimited, preferred examples thereof include hindered phenol, hinderedamine, quinone, hydroquinone, tocopherol, aspartic acid, thiol, citricacid, tocopheryl acetate, and tocopheryl phosphate per se, and salts orester compounds thereof.

One example of the antioxidant is shown below.

—Oxygen Getter—

A known substance used as a getter of an organic EL device can be usedas the oxygen getter. The oxygen getter may be either an inorganicgetter or an organic getter, and is preferable to include at least onecompound selected from a metal oxide, a metal halide, a metal sulfate, ametal perchlorate, a metal carbonate, a metal alkoxide, a metalcarboxylate, a metal chelate, or a zeolite (aluminosilicate).

Examples of such an oxygen getter include calcium oxide (CaO), bariumoxide (BaO), magnesium oxide (MgO), strontium oxide (SrO), lithiumsulfate (Li₂SO₄), sodium sulfate (Na₂SO₄), calcium sulfate (CaSO₄),magnesium sulfate (MgSO₄), cobalt sulfate (CoSO₄), gallium sulfate(Ga₂(SO₄)₃), titanium sulfate (Ti(SO₄)₂), and nickel sulfate (NiSO₄).

The organic getter is not particularly limited as long as it is amaterial that takes in water by a chemical reaction and does not becomeopaque before and after the reaction. Here, the organometallic compoundmeans a compound having a metal-carbon bond, a metal-oxygen bond, ametal-nitrogen bond or the like. In the case where water reacts with theorganometallic compound, the above-mentioned bond of the compound breaksdue to a hydrolysis reaction to result in a metal hydroxide. Dependingon the metal, hydrolytic polycondensation may be carried out to increasethe molecular weight after the reaction into the metal hydroxide.

As the metal of the metal alkoxide, the metal carboxylate, and the metalchelate, it is preferable to use a metal having good reactivity withwater as the organometallic compound, that is, a metal atom which iseasily breakable from a variety of bonds by the action of water.Specific examples thereof include aluminum, silicon, titanium,zirconium, bismuth, strontium, calcium, copper, sodium, and lithium. Inaddition, cesium, magnesium, barium, vanadium, niobium, chromium,tantalum, tungsten, chromium, indium, iron, and the like can bementioned. In particular, a desiccating agent of an organometalliccompound having aluminum as a central metal is preferable in terms ofdispersibility in a resin and reactivity with water. Examples of theorganic group include an unsaturated hydrocarbon such as a methoxygroup, an ethoxy group, a propoxy group, a butoxy group, a 2-ethylhexylgroup, an octyl group, a decyl group, a hexyl group, an octadecyl group,a stearyl group, a saturated hydrocarbon, a branched unsaturatedhydrocarbon, a branched saturated hydrocarbon, an alkoxy group orcarboxyl group containing a cyclic hydrocarbon, and a β-diketonato groupsuch as an acetoacetonato group or a dipivaloylmethanato group.

Among them, aluminum ethyl acetoacetates having 1 to 8 carbon atomsshown in the following chemical formulae are suitably used from theviewpoint that a sealing composition having excellent transparency canbe formed.

(in the formula, R₅ to R₈ each represent an organic group including analkyl group, an aryl group, an alkoxy group, a cycloalkyl group or anacyl group, each of which has 1 to 8 carbon atoms, and M represents atrivalent metal atom. In addition, R₅ to R₈ may be the same organicgroup or different organic group.)

The above-mentioned aluminum ethyl acetoacetates having 1 to 8 carbonatoms are commercially available, for example, from Kawaken FineChemical Co., Ltd. or Hope Pharmaceutical Co., Ltd.

The oxygen getter is in particulate or powder form. The average particlediameter of the oxygen getter may be usually in the range of less than20 μm, preferably 10 μm or less, more preferably 2 μm or less, and stillmore preferably 1 μm or less. From the viewpoint of scattering property,the average particle diameter of the oxygen getter is preferably 0.3 to2 μm and more preferably 0.5 to 1.0 μm. The term “average particlediameter” as used herein refers to an average value of particlediameters calculated from a particle size distribution measured by adynamic light scattering method.

—Polymerization Inhibitor—

The curable compound forming the resin layer 38 having impermeability tooxygen preferably contains a polymerization inhibitor. The content ofthe polymerization inhibitor is 0.001% to 1% by mass, more preferably0.005% to 0.5% by mass, and still more preferably 0.008% to 0.05% bymass, with respect to all the polymerizable monomers, and changes inviscosity over time can be suppressed while maintaining a high curingsensitivity by blending the polymerization inhibitor in an appropriateamount. The polymerization inhibitor may be added at the time ofproduction of the polymerizable monomer or may be added later to thecurable composition. Preferred examples of the polymerization inhibitorinclude hydroquinone, p-methoxyphenol, di-tert-butyl-p-cresol,pyrrogallol, tert-butylcatechol, benzoquinone,4,4′-thiobis(3-methyl-6-tert-butylphenol),2,2′-methylenebis(4-methyl-6-tert-butylphenol), cerousN-nitrosophenylhydroxyamine, phenothiazine, phenoxazine,4-methoxynaphthol, 2,2,6,6-tetramethylpiperidine-1-oxyl free radical,2,2,6,6-tetramethylpiperidine,4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical,nitrobenzene, and dimethylaniline, among which preferred isp-benzoquinone, 2,2,6,6-tetramethylpiperidine-1-oxyl free radical,4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, orphenothiazine. These polymerization inhibitors suppress generation ofpolymer impurities not only during the production of the polymerizablemonomers but also during storage of the curable composition and suppressdegradation of pattern formability during imprinting.

<<Resin Layer Having Impermeability to Oxygen>>

The resin layer 38 having impermeability to oxygen is formed by applyingand curing a resin forming coating liquid containing the above-mentionedcurable compound. The oxygen permeability at the shortest distancebetween adjacent fluorescent regions 35 of the resin layer 38 preferablysatisfies 10 cc/(m²·day·atm) or less. The oxygen permeability at theshortest distance between adjacent fluorescent regions 35 of the resinlayer 38 is more preferably 1 cc/(m²·day·atm) or less and still morepreferably 10⁻¹ cc/(m²·day·atm) or less. The shortest distance necessarybetween the fluorescent regions 35 varies depending on the compositionof the resin layer 38.

With respect to oxygen permeability, fm/(s·Pa) can be used as the SIunit. It is possible to carry out conversion of units as a relationshipof 1 fm/(s·Pa)=8.752 cc/(m²·day·atm). fm is read as femtometer and 1fm=10⁻¹⁵m.

Depending on the composition of the resin layer 38, the shortestdistance necessary between the fluorescent regions 35 varies. Theshortest distance between adjacent fluorescent regions 35 of the resinlayer 38 refers to the shortest distance in the film plane between theresin and the phosphor region in the case where it is observed from thephosphor-containing film main surface. In the following description, theshortest distance between adjacent fluorescent regions 35 of the resinlayer 38 may be referred to as the width of the resin layer.

As described above, the shortest distance necessary between the phosphorregions 35 varies depending on the composition of the resin layer 38,but as an example, the shortest distance between adjacent fluorescentregions 35 of the resin layer 38, that is, the width of the resin layeris preferably 0.001 mm or more and 3 mm or less, more preferably 0.01 mmor more and 2 mm or less, and particularly preferably 0.03 mm or moreand 2 mm or less. In the case where the width of the resin layer is tooshort, it is difficult to secure the necessary oxygen permeability, andin the case where the width of the resin layer is too long, luminanceunevenness of a display device deteriorates, which is not preferable.

The ratio of the volume Vp of the fluorescent region to the volume Vb ofthe resin layer can be arbitrary, but the ratio of the volume Vp of thefluorescent region to the volume (Vp+Vb) of the entirephosphor-containing layer is preferably 0.1≤Vp/(Vp+Vb)<0.9, morepreferably 0.2≤Vp/(Vp+Vb)<0.85, and particularly preferably0.3≤Vp/(Vp+Vb)<0.8. In the case where the volume ratio of thefluorescent region is too small, the initial luminance at a certainthickness tends to decrease, and in the case where the volume ratio ofthe fluorescent region is too large, the width of the resin layerbecomes short, and as a result, it becomes difficult to secure thenecessary oxygen permeability. Note that a region Vp containingphosphors and a region Vb of a resin layer having oxygen impermeabilityare defined as being multiplied by each area and thickness in the casewhere observed from the phosphor-containing film main surface.

The material for forming the resin layer 38 is preferably a compoundhaving a di- or higher functional photopolymerizable crosslinking group,and examples thereof include alicyclic (meth)acrylate such as urethane(meth)acrylate or tricyclodecanedimethanol di(meth)acrylate;(meth)acrylate having a hydroxyl group such as pentaerythritoltriacrylate; aromatic (meth)acrylate such as modified bisphenol Adi(meth)acrylate; dipentaerythritol di(meth)acrylate,3,4-epoxycyclohexylmethyl (meth)acrylate, 3′,4′-epoxycyclohexylmethyl3,4-epoxycyclohexane carboxylate, and bisphenol A type epoxy. Amongthem, it is preferable to include at least urethane (meth)acrylate andan epoxy compound from the viewpoint of enhancing the impermeability tooxygen. By using a compound having a urethane bond or a polar functionalgroup such as a hydroxyl group or a carboxyl group to enhanceintermolecular interaction, a resin layer having high impermeability tooxygen can be obtained. It is preferable to include a compound havingthe same polymerizable crosslinking group as that of the fluorescentregion from the viewpoint of excellent adhesion between the resin layerand the fluorescent region. For example, in the case wheredicyclopentanyl (meth)acrylate or the like is contained in the materialof the fluorescent region, the resin layer suitably contains at least a(meth)acrylate compound.

From the viewpoint of satisfying the condition that the formed resinlayer 38 has a Knoop hardness of 115 N/mm² to 285 N/mm², a creeprecovery rate of 22% or less, and an elastic recovery rate of 60% ormore, it is preferable to use a (meth)acrylate-based compound or anepoxy-based compound, in particular, a polyfunctional (meth)acrylatecompound or an epoxy (meth)acrylate compound, as the curable compound.

The curable compound for forming the resin layer 38 of the presentinvention having impermeability to oxygen may contain both a(meth)acrylate compound having an aromatic structure and/or an alicyclichydrocarbon structure and a (meth)acrylate having a fluorine atom as thepolymerizable compound. As for the compounding ratio, it is preferablethat 80% by mass or more of the total polymerizable compound componentis a (meth)acrylate compound having an aromatic structure and/or analicyclic hydrocarbon structure, and 0.1% to 10% by mass of the totalpolymerizable compound component is a (meth)acrylate having a fluorineatom. Further, preferred is a blend system in which the (meth)acrylatecompound having an aromatic structure and/or alicyclic hydrocarbonstructure is liquid at 1 atm and 25° C. and the (meth)acrylate having afluorine atom is solid at 1 atm and 25° C.

From the viewpoint of improving the curability and improving theviscosity of the curable compound, the total content of thepolymerizable compound in the curable compound forming the resin layer38 having impermeability to oxygen is preferably 50% to 99.5% by mass,more preferably 70% to 99% by mass, and particularly preferably 90% to99% by mass, in all the components excluding the solvent.

More preferably, as for the polymerizable compound component in thecurable compound forming the resin layer 38 having impermeability tooxygen, with respect to the total polymerizable compound, it ispreferable that the content of the polymerizable compound having aviscosity of 3 to 2,000 mPa·s at 25° C. is 80% by mass or more, it ismore preferable that the content of the polymerizable compound having aviscosity of 5 to 1,000 mPa·s at 25° C. is 80% by mass or more, it isparticularly preferable that the content of the polymerizable compoundhaving a viscosity of 7 to 500 mPa·s at 25° C. is 80% by mass or more,and it is most preferable that the content of the polymerizable compoundhaving a viscosity of 10 to 300 mPa·s at 25° C. is 80% by mass or more.

As for the polymerizable compound included in the curable compoundforming the resin layer 38 having impermeability to oxygen, it ispreferable that the polymerizable compound, which is liquid at 25° C.,is 50% by mass or more in the total polymerizable compound, from theviewpoint of temporal stability.

The curable compound forming the resin layer 38 having impermeability tooxygen is preferably a radical polymerizable curable composition inwhich the polymerizable compound is a radical polymerizable compound andthe photopolymerization initiator is a radical polymerization initiatorthat generates radicals upon irradiation with light.

The curable compound forming the resin layer 38 having impermeability tooxygen may contain at least one surfactant containing 20% by mass ormore of fluorine atoms.

The curable compound forming the resin layer 38 having impermeability tooxygen preferably contains a known oxygen getter.

In the curable compound forming the resin layer 38 having impermeabilityto oxygen, the oxygen getter is preferably 0.1% to 20% by mass, morepreferably 0.1% to 15% by mass, and still more preferably 0.1% to 10% bymass, with respect to the total mass of the curable compound.

Further, the curable compound forming the resin layer 38 havingimpermeability to oxygen preferably contains inorganic particles.Incorporation of inorganic particles can provide an enhancedimpermeability to oxygen. Examples of inorganic particles includeinorganic layered compounds such as silica particles, alumina particles,zirconium oxide particles, zinc oxide particles, titanium oxideparticles, mica, and talc. The inorganic particles are preferablyplate-like from the viewpoint of enhancing the impermeability to oxygen,and the aspect ratio (r=a/b, where a>b) of the inorganic particles ispreferably 2 or more and 1000 or less, more preferably 10 or more and800 or less, and particularly preferably 20 or more and 500 or less. Alarger aspect ratio is preferable because it has an excellent effect ofenhancing the impermeability to oxygen. However, in the case where theaspect ratio is too large, physical strength of a film or particledispersibility in a curing composition is poor.

In addition to the above-mentioned components, a releasing agent, asilane coupling agent, an ultraviolet absorber, a light stabilizer, ananti-aging agent, a plasticizer, an adhesion promoter, a thermalpolymerization initiator, a colorant, elastomer particles, a photoacidproliferating agent, a photobase generator, a basic compound, a flowadjusting agent, an anti-foaming agent, a dispersant, or the like may beadded to the curable compound forming the resin layer 38 havingimpermeability to oxygen.

The method for preparing the curable composition forming the resin layer38 having impermeability to oxygen is not particularly limited, and itmay be carried out by a procedure for preparing a common curablecomposition.

—Substrate Film—

The first substrate film 10 and the second substrate film 20 arepreferably a film having a function of suppressing permeation of oxygen.The above-mentioned embodiment has a configuration in which the barrierlayers 12 and 22 are provided on one surface of the support films 11 and21, respectively. In such an embodiment, the presence of the supportfilms 11 and 21 improves the strength of the phosphor-containing filmand makes it possible to easily perform film formation. In the presentembodiment, the barrier layers 12 and 22 are provided on one surface ofthe support films 11 and 21, but the substrate film may be constitutedby only a support having sufficient barrier properties.

The first substrate film 10 and the second substrate film 20 have atotal light transmittance in the visible light region of preferably 80%or more and more preferably 85% or more. The visible light region refersto a wavelength range of 380 to 780 nm, and the total lighttransmittance refers to an average value of light transmittances overthe visible light region.

The oxygen permeability of the first substrate film 10 and the secondsubstrate film 20 is preferably 1.00 cc/(m²·day·atm) or less. The oxygenpermeability is more preferably 0.1 cc/(m²·day·atm) or less, still morepreferably 0.01 cc/(m²·day·atm) or less, and particularly preferably0.001 cc/(m²·day·atm) or less. The oxygen permeability here is a valuemeasured using an oxygen gas permeability measuring apparatus (OX-TRAN2/20, trade name, manufactured by MOCON Inc.) under conditions of ameasurement temperature of 23° C. and a relative humidity of 90%.

In addition to having a gas barrier function of blocking oxygen, thefirst substrate film 10 and the second substrate film 20 preferably havea function of blocking moisture (water vapor). The moisture permeability(water vapor permeability) of the first substrate film 10 and the secondsubstrate film 20 is preferably 0.10 g/(m²·day·atm) or less and morepreferably 0.01 g/(m²·day·atm) or less.

(Support Film)

The support films 11 and 21 are preferably a flexible belt-like supportwhich is transparent to visible light. The phrase “transparent tovisible light” as used herein refers to a light transmittance in thevisible light region of 80% or more and preferably 85% or more. Thelight transmittance for use as a measure of transparency can becalculated by the method described in JIS-K7105, namely, by measuring atotal light transmittance and an amount of scattered light using anintegrating sphere type light transmittance measuring apparatus, andsubtracting the diffuse transmittance from the total lighttransmittance. With respect to the flexible support, reference can bemade to paragraphs [0046] to [0052] of JP2007-290369A and paragraphs[0040] to [0055] of JP2005-096108A.

The support film preferably has barrier properties against oxygen andmoisture. Preferred examples of such a support film include apolyethylene terephthalate film, a film made of a polymer having acyclic olefin structure, and a polystyrene film.

From the viewpoint of gas barrier properties, impact resistance, and thelike, the thickness of the support film is in the range of 10 to 500 μm,inter alia, preferably in the range of 15 to 300 μm, particularlypreferably in the range of 15 to 120 μm, more particularly preferably inthe range of 15 to 100 μm, further preferably 25 to 110 μm, and mostpreferably 25 to 60 μm.

Further, in the support films 11 and 21, the in-plane retardation Re(589) at a wavelength of 589 nm is preferably 1000 nm or less, morepreferably 500 nm or less, and still more preferably 200 nm or less.

In the case of inspecting the presence or absence of foreign matters anddefects after preparing the phosphor-containing film, arranging twopolarizing plates at the extinction position, inserting aphosphor-containing film therebetween and observing it makes it easy tofind foreign matters and defects. In the case where the Re (589) of thesupport is within the above range, foreign matters and defects are moreeasily found at the time of inspection using a polarizing plate, whichis thus preferable.

Here, the Re (589) can be measured by making light having an inputwavelength of 589 nm incident in the normal direction of the film usingan AxoScan OPMF-1 (manufactured by Opto Science, Inc.).

(Barrier Layer)

The first substrate film 10 and the second substrate film 20 preferablycomprise barrier layers 12 and 22 containing at least one inorganiclayer formed in contact with the surface of the support films 11 and 21on the phosphor-containing layer 30 side. The barrier layers 12 and 22may include at least one inorganic layer and at least one organic layer.Lamination of a plurality of layers in this way is preferable from theviewpoint of improving the light resistance due to being capable offurther more enhancing barrier properties. On the other hand, the lighttransmittance of the substrate film tends to decrease as the number oflayers to be laminated is increased, and therefore it is desirable toincrease the number of laminated layers as long as a satisfactory lighttransmittance can be maintained.

Specifically, the barrier layers 12 and 22 preferably have a total lighttransmittance in the visible light region of preferably 80% or more andan oxygen permeability of 1.00 cc/(m²·day·atm) or less.

The oxygen permeability of the barrier layers 12 and 22 is morepreferably 0.1 cc/(m²·day·atm) or less, particularly preferably 0.01cc/(m²·day·atm) or less, and more particularly preferably 0.001cc/(m²·day·atm) or less.

A lower oxygen permeability is more preferable, and a higher total lighttransmittance in the visible light region is more preferable.

The inorganic layer is a layer containing an inorganic material as amain component, and preferably a layer formed from only an inorganicmaterial.

The inorganic layer is preferably a layer having a gas barrier functionof blocking oxygen. Specifically, the oxygen permeability of theinorganic layer is preferably 1.00 cc/(m²·day·atm) or less. The oxygenpermeability of the inorganic layer can be determined by attaching awavelength converting layer to a detector of an oxygen concentrationmeter manufactured by Orbisphere Laboratories, via silicone grease, andthen converting the oxygen permeability from the equilibrium oxygenconcentration value. It is also preferable that the inorganic layer hasa function of blocking water vapor.

Two or three or more inorganic layers may also be included in thebarrier layer.

The thickness of the inorganic layer may be 1 to 500 nm, and ispreferably 5 to 300 nm and particularly preferably 10 to 150 nm. This isbecause the film thickness of an adjacent inorganic layer in the aboverange is capable of suppressing reflection on the inorganic layer whileachieving satisfactory barrier properties, whereby a laminated film withhigher light transmittance can be provided.

In the substrate film, it is preferable that at least one inorganiclayer adjacent to the phosphor-containing layer is included.

The inorganic material constituting the inorganic layer is notparticularly limited, and for example, a metal, or various inorganiccompounds such as inorganic oxides, nitrides or oxynitrides can be usedtherefor. For element(s) constituting the inorganic material, silicon,aluminum, magnesium, titanium, tin, indium, and cerium are preferable,and these elements may be included singly or two or more thereof may beincluded. Specific examples of the inorganic compound include siliconoxide, silicon oxynitride, aluminum oxide, magnesium oxide, titaniumoxide, tin oxide, an indium oxide alloy, silicon nitride, aluminumnitride, and titanium nitride. As the inorganic layer, a metal film, forexample, an aluminum film, a silver film, a tin film, a chromium film, anickel film, or a titanium film may also be provided.

It is particularly preferable that the inorganic layer having barrierproperties is an inorganic layer containing at least one compoundselected from silicon nitride, silicon oxynitride, silicon oxide, oraluminum oxide, among the above-mentioned materials. This is because theinorganic layer formed of such a material is satisfactory inadhesiveness to the organic layer, and therefore, not only, even in thecase where the inorganic layer has a pinhole, the organic layer caneffectively fill in the pinhole to suppress fracture, but also, even inthe case where the inorganic layer is laminated, an extremelysatisfactory inorganic layer film can be formed to result in a furtherenhancement in barrier properties.

The method for forming an inorganic layer is not particularly limited,and for example, a variety of film forming methods capable ofevaporating or scattering a film forming material and depositing it onthe deposition target surface can be used.

Examples of the method of forming an inorganic layer include a physicalvapor deposition method (PVD method) such as a vacuum vapor depositionmethod of heating an inorganic material such as an inorganic oxide, aninorganic nitride, an inorganic oxynitride, or a metal to cause vapordeposition thereof; an oxidation reaction vapor deposition method ofusing an inorganic material as a starting material and introducingoxygen gas for oxidation to cause vapor deposition thereof; a sputteringmethod of using an inorganic material as a target starting material andintroducing argon gas or oxygen gas for sputtering to cause vapordeposition; or an ion plating method of causing heating of an inorganicmaterial by a plasma beam generated by a plasma gun to cause vapordeposition; and a plasma chemical vapor deposition method (CVD method)of using an organosilicon compound as a starting material in the case offorming a vapor deposited film of silicon oxide.

The organic layer refers to a layer containing an organic material as amain component, in which the organic material preferably occupies 50% bymass or more, further preferably 80% by mass or more, and particularlypreferably 90% by mass or more.

With respect to the organic layer, reference can be made to paragraphs[0020] to [0042] of JP2007-290369A and paragraphs [0074] to [0105] ofJP2005-096108A. It is preferable that the organic layer contains a cardopolymer within a range satisfying the above-mentioned adhesion forceconditions. This is because adhesiveness to the layer adjacent to theorganic layer, in particular, also adhesiveness to the inorganic layercan be thus improved to achieve excellent gas barrier properties. Withrespect to details of the cardo polymer, reference can be made toparagraphs [0085] to [0095] of JP2005-096108A described above. The filmthickness of the organic layer is preferably in the range of 0.05 to 10μm, inter alia, more preferably in the range of 0.5 to 10 μm. In thecase where the organic layer is formed by a wet coating method, the filmthickness of the organic layer is preferably in the range of 0.5 to 10μm, inter alia, preferably in the range of 1 to 5 μm. In the case wherethe organic layer is formed by a dry coating method, the film thicknessof the organic layer is preferably in the range of 0.05 to 5 μm, interalia, preferably in the range of 0.05 to 1 μm. This is because the filmthickness of the organic layer formed by a wet coating method or a drycoating method in the above-specified range is capable of furtherimproving adhesiveness to the inorganic layer.

With respect to other details of the inorganic layer and the organiclayer, reference can be made to the descriptions of JP2007-290369A andJP2005-096108A described above and US2012/0113672A1.

In the phosphor-containing film, the organic layer may be laminated asthe underlayer of the inorganic layer between the support film and theinorganic layer, and may be laminated as the protective layer of theinorganic layer between the inorganic layer and the phosphor-containinglayer. Further, in the case of having two or more inorganic layers, theorganic layer may be laminated between the inorganic layers.

(Concavity-Convexity Imparting Layer)

The substrate films 10 and 20 may be provided with a concavity-convexityimparting layer for imparting a concave-convex structure on the surfaceopposite to the surface on the phosphor-containing layer 30 side. In thecase where the substrate films 10 and 20 have a concavity-convexityimparting layer, the blocking property and sliding property of thesubstrate film can be improved, which is thus preferable. Theconcavity-convexity imparting layer is preferably a layer containingparticles. Examples of the particles include inorganic particles such assilica, alumina, or metal oxide, and organic particles such ascrosslinked polymer particles. The concavity-convexity imparting layeris preferably provided on the surface opposite to thephosphor-containing layer of the substrate film, but it may be providedon both surfaces.

The phosphor laminate film can have a light scattering function toefficiently extract the fluorescence of quantum dots to the outside. Thelight scattering function may be provided inside the phosphor-containinglayer 30 or a layer having a light scattering function may be separatelyprovided as the light scattering layer. The light scattering layer maybe provided on the surface on the side of the phosphor-containing layer30 of the substrate films 10 and 20 or may be provided on the surface onthe side opposite to the phosphor-containing layer 30 of the substratefilms 10 and 20. In the case where the concavity-convexity impartinglayer is provided, it is preferable that the concavity-convexityimparting layer is a layer which can also serve as the light scatteringlayer.

<Production Method of Phosphor-Containing Film>

Next, an example of production steps of the phosphor-containing filmaccording to the embodiment of the present invention configured asdescribed above will be described with reference to FIGS. 11 and 12.

(Coating Liquid Preparation Step)

In the first coating liquid preparation step, a coating liquid forforming a fluorescent region containing quantum dots (or quantum rods)as phosphors is prepared. Specifically, individual components such asquantum dots, a curable compound, a polymer dispersant, a polymerizationinitiator, and a silane coupling agent dispersed in an organic solventare mixed in a tank or the like to prepare a coating liquid for forminga fluorescent region. Note that the coating liquid for forming afluorescent region may not contain an organic solvent.

In the second coating liquid preparation step, a coating liquid for aresin layer to be filled between the fluorescent regions is prepared.

(Resin Layer Forming Step)

Next, a coating liquid for a resin layer is applied onto the firstsubstrate film 10, and a mold having a concavo-convex pattern is pressedagainst the applied coating liquid for a resin layer to form apredetermined pattern having a concave portion, and the coating liquidfor a resin layer is cured to form a laminated film 59 in which theresin layer 38 having a plurality of concave portions is laminated onthe first substrate film 10, as shown in FIG. 11.

(Fluorescent Region Forming Step and Second Substrate Film Bonding Step)

Next, the coating liquid for forming a fluorescent region is appliedinto the concave portion of the resin layer 38 of the laminated film 59,the second substrate film 20 is bonded before curing the coating liquidfor forming a fluorescent region, and then the coating liquid forforming a fluorescent region is cured to form a fluorescent region 35 toprepare a phosphor-containing film in which the first substrate film 10,the phosphor-containing layer 30, and the second substrate film 20 arelaminated.

With respect to the curing treatment in the fluorescent region formingstep and the resin layer forming step, thermal curing, photocuring withultraviolet rays, or the like may be appropriately selected depending onthe coating liquid.

In the case where the resin layer 38 is cured by photocuring withultraviolet rays, the irradiation amount of ultraviolet rays ispreferably 100 to 10000 mJ/cm².

In the case where the resin layer 38 is cured by thermal curing, it ispreferable to heat the resin layer 38 to 20° C. to 100° C.

(Cutting Process)

A continuous (long) phosphor-containing film can be obtained byperforming the above steps in a roll-to-roll type apparatus. Theobtained phosphor-containing film is cut by a cutting machine asnecessary.

Although a method of preparing a phosphor-containing film by an R to Rprocess has been described, the treatment of each step may be carriedout in a so-called single wafer type, using a substrate film in the formof a cut sheet.

Further, the above example is configured such that the resin layer 38 isformed and is once wound into a roll shape, and then the fluorescentregion 35 or the like is formed, but the present invention is notlimited thereto. The preparation of a phosphor-containing film may beconfigured such that the resin layer 38 is formed and continuouslytransported, and then the fluorescent region 35 or the like is formed.

Here, in the case where the resin layer forming step is carried outbefore the fluorescent region forming step, that is, in the case wherethe resin layer 38 having impermeability to oxygen is formed prior tothe fluorescent region, a method of forming a pattern (in particular, afine convex and concave pattern) using a curable compound for formingthe resin layer 38 will be described.

To form a pattern, a so-called photoimprinting method of forming a fineconvex and concave pattern through a step of applying a curable compoundforming a resin layer 38 having impermeability to oxygen onto asubstrate or a support (base material), a step of pressing a moldagainst the surface of the coating layer, a step of irradiating thecurable compound with light, and a step of peeling a mold can be used.

Here, the curable compound forming the resin layer 38 havingimpermeability to oxygen may be poured between the base material and themold, and then photo-cured while pressing the mold under pressure.Further, the curable compound may be further heated and cured afterphoto-irradiation. Such photoimprint lithography is also capable ofachieving lamination or multiple patterning and may be used incombination with thermal imprinting.

The pattern formation can also be carried out by an inkjet method or adispenser method.

Hereinafter, the convex and concave pattern forming method (patterntransfer method) will be specifically described.

First, a curable compound is applied onto a base material. The methodsof applying a curable compound onto the base material include commonlywell-known application methods such as dip coating, air knife coating,curtain coating, wire bar coating, gravure coating, extrusion coating,spin coating, slit scanning, casting, and ink jet methods, by which acoated film or liquid droplets may be applied onto the base material.The curable compound forming the resin layer 38 having impermeability tooxygen is suitable for a gravure coating method and a casting method.The film thickness of the pattern forming layer (coating layer forforming a pattern) formed of the curable compound varies depending onthe application to be used, but it is about 1 to 150 μm. Alternatively,the curable compound may be coated by multiple coating. Further, anotherorganic layer such as a planarizing layer may be formed between the basematerial and the pattern forming layer. The pattern forming layer andthe substrate are therefore not brought into direct contact with eachother, so that the substrate may be prevented from adhesion of dust,damage, and the like.

The base material (substrate or support) for applying a curable compoundis selectable depending on various applications, and examples thereofinclude, but are not particularly limited to, quartz, glass, opticalfilm, ceramic material, vapor deposited film, magnetic film, reflectivefilm, metal substrate made of Ni, Cu, Cr, Fe or the like, paper, Spin OnGlass (SOG), polymer substrates such as polyester film, polycarbonatefilm, or polyimide film, thin film transistor (TFT) array substrate,electrode plate of plasma display panel (PDP), glass or transparentplastic substrate, electro-conductive base material made of indium tinoxide (ITO), metal, or the like, insulating base material, andsemiconductor manufacturing substrate made of silicon, silicon nitride,polysilicon, silicon oxide, amorphous silicon, or the like. The shape ofthe base material is also not particularly limited, and may be any of aplate-like substrate or a roll-like substrate. Further, as describedbelow, the base material may be selected from light-transmissive andnon-light-transmissive ones, depending on a combination with a mold orthe like.

Next, in order to transfer the pattern to the pattern forming layer, themold is pressed onto the surface of the pattern forming layer. In thisway, a fine pattern preliminarily formed on the surface, to be pressed,of the mold may be transferred to the pattern forming layer.Alternatively, a curable compound may be applied onto a mold having apattern formed thereon, and the substrate may be pressed thereto. Forphotoimprint lithography, a light-transmissive material is selected forat least one of the molding material and/or the base material. In thephotoimprint lithography, a curable compound is applied onto a basematerial to form a pattern forming layer thereon, and alight-transmissive mold is pressed against the surface of the patternforming layer, then this is irradiated with light from the back of themold, and the curable compound is thereby cured. Alternatively, acurable compound is applied onto a light-transmissive base material,then a mold is pressed against the surface of the coating layer, andthis is irradiated with light from the back of the base material wherebythe curable compound can be cured.

The photo-irradiation may be carried out in a state in which the mold isattached or after the mold is released, but it is preferable to performphoto-irradiation in a state where the mold is closely attached.

The mold usable herein is a mold having formed thereon a pattern to betransferred. The pattern on the mold may be formed according to desiredprocessing accuracy, for example, by photolithography, electron beamlithography, or the like, but the method of forming a mold pattern isnot particularly limited.

The light-transmissive molding material is not particularly limited, butany material having predetermined strength and durability may be used.Specific examples thereof include glass, quartz, a light-transparentresin such as PMMA or polycarbonate resin, a transparent metalvapor-deposited film, a flexible film made of polydimethylsiloxane orthe like, a photocured film, and a metal film such as SUS.

On the other hand, the non-light-transmissive molding material used inthe case of using a light-transmissive base material is not particularlylimited, but any material having a predetermined strength may be used.Specific examples of the molding material include a ceramic material, avapor deposited film, a magnetic film, a reflective film, a metalsubstrate such as Ni, Cu, Cr, Fe or the like, and a substrate of SiC,silicon, silicon nitride, polysilicon, silicon oxide, amorphous siliconor the like. Further, the shape of the mold is not particularly limited,either a plate-like mold or a roll-like mold may be used. The roll-likemold is applied particularly in the case where continuous productivityof transfer is required.

A mold may be used which has been subjected to a surface releasetreatment in order to improve releasability between the curable compoundand the mold surface. As such a mold, those treated with a silanecoupling agent such as a silicone-based silane coupling agent or afluorine-based silane coupling agent, for example, commerciallyavailable releasing agents such as OPTOOL DSX (manufactured by DaikinIndustries, Ltd.) and Novec EGC-1720 (manufactured by Sumitomo 3M Ltd.)can also be suitably used.

In the case where such photoimprint lithography is carried out, it isusually preferable to carry out the lithography at a mold pressure of 10atm or less. In the case where the mold pressure is set to 10 atm orless, the mold and the substrate are hardly deformed and the patternaccuracy tends to improve. In addition, it is preferable from theviewpoint that the pressure unit may be small-sized since the pressureto be given to the mold may be low. Regarding the mold pressure, it ispreferable to select a region where uniformity of mold transfer can besecured within the range where the residual film of the curable compoundin the area of mold pattern projections is reduced.

The irradiation dose of photo-irradiation in the step of irradiating thepattern forming layer with light may be sufficiently larger than theirradiation dose necessary for curing. The irradiation dose necessaryfor curing is appropriately determined by examining the consumptionamount of unsaturated bonds of the curable composition and the tackinessof the cured film.

In the photoimprint lithography, photo-irradiation is carried out whilekeeping the substrate temperature generally at room temperature, inwhich the photo-irradiation may alternatively be conducted under heatingfor the purpose of enhancing the reactivity. The photo-irradiation maybe carried out in vacuo, since a vacuum conditioning prior to thephoto-irradiation is effective for preventing entrainment of bubbles,suppressing the reactivity from being reduced due to incorporation ofoxygen, and for improving the adhesiveness between the mold and thecurable composition. In the pattern forming method, the degree of vacuumat the time of photo-irradiation is preferably in the range of 10⁻¹ Pato 1 atmosphere.

The light used for curing the curable compound is not particularlylimited, and examples thereof include light and radiation having awavelength falling within a range of high-energy ionizing radiation,near ultraviolet light, far ultraviolet light, visible light, infraredlight, and the like. The high-energy ionizing radiation source includes,for example, accelerators such as a Cockcroft accelerator, a Van deGraaff accelerator, a linear accelerator, a betatron, and a cyclotron.The electron beams accelerated by such an accelerator are usedindustrially most conveniently and economically; but any otherradioisotopes and other radiations from nuclear reactors, such asγ-rays, X-rays, α-rays, neutron beams, and proton beams may also beused. Examples of the ultraviolet ray source include an ultravioletfluorescent lamp, a low-pressure mercury lamp, a high-pressure mercurylamp, an ultra-high-pressure mercury lamp, a xenon lamp, a carbon arclamp, a solar lamp, and a light emitting diode (LED). Examples of theradiation include microwaves and extreme ultraviolet (EUV). In addition,laser light used in microfabrication of semiconductors, such as LED,semiconductor laser light, 248 nm KrF excimer laser light, and 193 nmArF excimer laser light, can also be suitably used in the presentinvention. These light rays may be monochromatic light, or may also be aplurality of light rays of different wavelengths (mixed light).

Upon exposure, the exposure illuminance is preferably within a range of1 mW/cm² to 50 mW/cm². In the case where the exposure illuminance is setto 1 mW/cm² or more, then the productivity may increase since theexposure time may be reduced; and in the case where the exposureilluminance is set to 50 mW/cm² or less, then it is preferable since theproperties of a permanent film may be prevented from being degradedowing to side reactions. The exposure dose is preferably in the range of5 mJ/cm² to 1,000 mJ/cm². In the case where the exposure dose is lessthan 5 mJ/cm², the exposure margin becomes narrow and the photocuringbecomes insufficient so that problems such as adhesion of unreactedmaterials to the mold are liable to occur. On the other hand, in thecase where the exposure dose is more than 1,000 mJ/cm², there is a riskof deterioration of the permanent film due to decomposition of thecomposition. Further, at the time of exposure, in order to preventinhibition of radical polymerization by oxygen, an inert gas such asnitrogen or argon may be flowed to control the oxygen concentration tobe less than 100 mg/L.

In the pattern forming method, after the pattern forming layer is curedthrough photo-irradiation, a step of further curing the cured pattern byapplying heat thereto may be included as necessary. The temperature ofheat for heating and curing the composition of the present inventionafter photo-irradiation is preferably 150° C. to 280° C. and morepreferably 200° C. to 250° C. The heating time is preferably 5 to 60minutes and more preferably 15 to 45 minutes.

The pattern to be formed may take an arbitrary form. For example, thereis a grid-like mesh pattern in which a concave or convex portion is of aregular tetragon, a honeycomb pattern in which a concave or convexportion is of a regular hexagon, or a sea island pattern in which aconcave or convex portion is circular. A honeycomb pattern having aphosphor-containing layer in a regular hexagonal portion and a resinlayer in a peripheral portion is particularly preferable from theviewpoint of effectively blocking penetration of oxygen into a phosphorlayer with respect to an arbitrary cutting form of the presentinvention.

“Backlight Unit”

With reference to the drawings, a description will be given of abacklight unit comprising a wavelength converting member as oneembodiment of the phosphor-containing film of the present invention.FIG. 13 is a schematic diagram showing a schematic configuration of abacklight unit.

As shown in FIG. 13, the backlight unit 102 comprises a planar lightsource 101C including a light source 101A that emits primary light (bluelight L_(B)) and a light guide plate 101B that guides and emits primarylight emitted from the light source 101A, a wavelength converting member100 made of a phosphor-containing film provided on the planar lightsource 101C, a reflecting plate 102A disposed opposite to the wavelengthconverting member 100 with the planar light source 101C interposedtherebetween, and a retroreflective member 102B. In FIG. 13, thereflecting plate 102A, the light guide plate 101B, the wavelengthconverting member 100, and the retroreflective member 102B are separatedfrom each other, but in reality these may be formed in intimateattachment with each other.

The wavelength converting member 100 emits fluorescence by using atleast a part of the primary light L_(B) emitted from the planar lightsource 101C as excitation light and emits the secondary light (greenlight L_(G) and red light L_(R)) composed of this fluorescence and theprimary light L_(B) transmitted through the wavelength converting member100. For example, the wavelength converting member 100 is aphosphor-containing film which is constituted such that thephosphor-containing layers including the quantum dots that emit thegreen light L_(G) and the quantum dots that emit the red light L_(R)upon irradiation with the blue light L_(B) are sandwiched between thefirst substrate film and the second substrate film.

In FIG. 13, L_(B), L_(G), and L_(R) emitted from the wavelengthconverting member 100 are incident on the retroreflective member 102B,and each incident light repeats reflection between the retroreflectivemember 102B and the reflecting plate 102A and passes through thewavelength converting member 100 many times. As a result, in thewavelength converting member 100, a sufficient amount of excitationlight (blue light L_(B)) is absorbed by the phosphors 31 (in this case,quantum dots) in the phosphor-containing layer 30 and a necessary amountof fluorescence (L_(G) and L_(R)) is emitted, and the white light Lw isembodied from the retroreflective member 102B and is emitted.

From the viewpoint of realizing high luminance and high colorreproducibility, it is preferable to use, as the backlight unit, oneformed into a multi-wavelength light source. For example, preferred is abacklight unit which emits blue light having a luminescence centerwavelength in the wavelength range of 430 to 480 nm and having aluminescence intensity peak with a half-width of 100 nm or less, greenlight having a luminescence center wavelength in the wavelength range of500 to 600 nm and having a luminescence intensity peak with a half-widthof 100 nm or less, and red light having a luminescence center wavelengthin the wavelength range of 600 nm to 680 nm and having a luminescenceintensity peak with a half-width of 100 nm or less.

From the viewpoint of further improving luminance and colorreproducibility, the wavelength range of the blue light emitted from thebacklight unit is more preferably 440 nm to 460 nm.

From the same viewpoint, the wavelength range of the green light emittedfrom the backlight unit is preferably 520 nm to 560 nm and morepreferably 520 nm to 545 nm.

In addition, from the same viewpoint, the wavelength range of the redlight emitted from the backlight unit is more preferably 610 nm to 650nm.

In addition, from the same viewpoint, all the half-widths of therespective luminescence intensities of the blue light, the green light,and the red light emitted from the backlight unit are preferably 80 nmor less, more preferably 50 nm or less, further preferably 40 nm orless, still more preferably 30 nm or less. Among them, the half-width ofthe luminescence intensity of the blue light is particularly preferably25 nm or less.

In the above description, the light source 101A is, for example, a bluelight emitting diode that emits blue light having a luminescence centerwavelength in the wavelength range of 430 nm to 480 nm, but anultraviolet light emitting diode that emits ultraviolet light may beused. An ultraviolet light emitting diode is a light emitting diodehaving a light emission center in a wavelength range of 350 nm to 400nm, for example. As the light source 101A, a laser light source or thelike may be used in addition to light emitting diodes. In the case wherea light source that emits ultraviolet light is provided, the wavelengthconverting layer (phosphor-containing layer) of the wavelengthconverting member may include a phosphor that emits blue light, aphosphor that emits green light, and a phosphor that emits red light,upon irradiation with ultraviolet light.

As shown in FIG. 13, the planar light source 101C may be a planar lightsource formed of the light source 101A, and the light guide plate 101Bwhich guides the primary light exiting from the light source 101A andallows the guided primary light to exit, or may be a planar light sourcein which the light source 101A and the wavelength converting member 100are disposed parallel to each other on the plane, and a diffusion plateis provided in place of the light guide plate 101B. The former planarlight source is generally referred to as an edge light mode backlightunit, and the latter planar light source is generally referred to as adirect backlight mode backlight unit.

In the present embodiment, the case where a planar light source is usedas a light source has been described as an example, but a light sourceother than the planar light source may also be used as the light source.

(Configuration of Backlight Unit)

In FIG. 13, an edge light mode backlight unit including a light guideplate, a reflecting plate, and the like as constituent members has beenillustrated as the configuration of the backlight unit, but thebacklight unit may be a direct backlight mode backlight unit. A knownlight guide plate can be used without any limitation as the light guideplate.

In addition, the reflecting plate 102A is not particularly limited, andknown reflecting plates can be used, which are described in JP3416302B,JP3363565B, JP4091978B, and JP3448626B, and the like, the contents ofwhich are incorporated by reference herein in their entirety.

The retroreflective member 102B may be configured of a known diffusionplate or a known diffusion sheet, a known prism sheet (for example, BEFseries manufactured by Sumitomo 3M Limited), a known light guide device,and the like. The configuration of the retroreflective member 102B isdescribed in JP3416302B, JP3363565B, JP4091978B, JP3448626B, and thelike, the contents of which are incorporated by reference herein intheir entirety.

“Liquid Crystal Display”

The backlight unit 102 described above can be applied to a liquidcrystal display. As shown in FIG. 14, a liquid crystal display 104comprises the backlight unit 102 of the above-described embodiment, anda liquid crystal cell unit 103 disposed opposite to the retroreflectivemember side of the backlight unit.

As shown in FIG. 14, the liquid crystal cell unit 103 has aconfiguration in which a liquid crystal cell 110 is sandwiched betweenpolarizing plates 120 and 130, and the polarizing plates 120 and 130 areconfigured such that both main surfaces of polarizers 122 and 132 areprotected by polarizing plate protective films 121 and 123, and 131 and133, respectively.

The liquid crystal cell 110 and the polarizing plates 120 and 130constituting the liquid crystal display 104 and the constituents thereofare not particularly limited, and members prepared by a known method orcommercially available products can be used without any limitation. Inaddition, it is also possible, of course, to provide a knownintermediate layer such as an adhesive layer between the respectivelayers.

A driving mode of the liquid crystal cell 110 is not particularlylimited, and various modes such as a twisted nematic (TN) mode, a supertwisted nematic (STN) mode, a vertical alignment (VA) mode, an in-planeswitching (IPS) mode, and an optically compensated bend cell (OCB) modecan be used. The driving mode of the liquid crystal cell is preferably aVA mode, an OCB mode, an IPS mode, or a TN mode, but it is not limitedthereto. An example of the configuration of the liquid crystal displayin the VA mode may be the configuration illustrated in FIG. 2 ofJP2008-262161A. Here, a specific configuration of the liquid crystaldisplay is not particularly limited, and a known configuration can beadopted.

Further, as necessary, the liquid crystal display 104 includes asubsidiary functional layer such as an optical compensation memberperforming optical compensation or an adhesive layer. In addition, asurface layer such as a forward scattering layer, a primer layer, anantistatic layer, or an undercoat layer may be disposed along with (orin place of) a color filter substrate, a thin layer transistorsubstrate, a lens film, a diffusion sheet, a hard coat layer, anantireflection layer, a low reflective layer, an antiglare layer, or thelike.

The backlight side polarizing plate 120 may include a phase differencefilm as a polarizing plate protective film 123 on the liquid crystalcell 110 side. A known cellulose acylate film or the like can be used assuch a phase difference film.

The backlight unit 102 and the liquid crystal display 104 are providedwith the wavelength converting member made of the phosphor-containingfilm according to the embodiment of the present invention describedabove in which oxygen deterioration is suppressed. Accordingly, the sameeffect as that of the above-mentioned phosphor-containing film accordingto the embodiment of the present invention can be obtained, and ahigh-luminance backlight unit and a high-luminance liquid crystaldisplay, in which the luminescence intensity of the wavelengthconverting layer containing quantum dots is hardly lowered, areobtained.

EXAMPLES

Hereinafter, the present invention will be more specifically describedwith reference to Examples. The materials, use amounts, proportions,treatment contents, treatment procedures, and the like shown in thefollowing Examples can be appropriately modified without departing fromthe spirit of the present invention. Therefore, the scope of the presentinvention should not be construed as being limited to the followingspecific Examples.

Example 1

<Preparation of Phosphor-Containing Film>

A phosphor-containing film having a phosphor-containing layer wasprepared using a coating liquid containing quantum dots as a phosphor.

(Substrate Film)

As a first substrate film and a second substrate film, a substrate filmwas prepared in which a barrier layer made of an inorganic layer wasformed on a support film made of polyethylene terephthalate (PET), andan organic layer coated with the following composition was formed on thebarrier layer. The material for forming the inorganic layer was siliconnitride (Si₃N₄), and the thickness thereof was 30 nm. In the case wherethe oxygen permeability of the substrate film was measured using OX-TRAN2/20 (manufactured by MOCON Inc.), it showed a value of 4.0×10⁻³cc/(m²·day·atm) or less.

((Composition for Substrate Film Organic Layer))

Urethane acrylate 30 parts by mass (ACRIT 8BR-500, manufactured byTaisei Fine Chemical Co., Ltd.) Photopolymerization initiator  3 partsby mass (IRGACURE 184, manufactured by BASF Corporation) Methyl isobutylketone 67 parts by mass

The above composition was coated on the barrier layer of the supportfilm to a thickness of 1 μm and then dried at 60° C. for 1 minute. Usingan air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.)at 200 W/cm, ultraviolet rays at a dose of 400 mJ/cm² were irradiatedfrom the coated surface to cure the dried film, thus forming an organiclayer.

(Preparation of Phosphor-Containing Layer)

As a coating liquid 1 for forming a phosphor-containing layer,individual components such as a quantum dot, a curable compound, athixotropic agent, a polymerization initiator, and a silane couplingagent were mixed in a tank or the like to prepare a coating liquid.

<Composition of Coating Liquid 1 of Phosphor-Containing Layer>

A quantum dot dispersion liquid having the following composition wasprepared and used as coating liquid 1.

Toluene dispersion liquid of quantum 10 parts by mass dots 1 (emissionmaximum: 520 nm) Toluene dispersion liquid of quantum 1 part by massdots 2 (emission maximum: 630 nm) Lauryl methacrylate 2.4 parts by massTrimethylolpropane triacrylate 0.54 parts by mass Photopolymerizationinitiator 0.009 parts by mass (IRGACURE 819, manufactured by BASFCorporation)

For the quantum dots 1 and 2, nanocrystals having the followingcore-shell structure (InP/ZnS) were used.

-   -   Quantum dots 1: INP 530-10 (manufactured by NN-Labs, LLC)    -   Quantum dots 2: INP 620-10 (manufactured by NN-Labs, LLC)

<Composition of Coating Liquid for Forming Resin Layer>

A coating liquid for forming a resin layer having the followingcomposition was prepared to obtain a coating liquid 2.

Urethane (meth)acrylate (U-4HA, manufactured 49 parts by mass byShin-Nakamura Chemical Co., Ltd.) Tricyclodecanedimethanol diacrylate 25parts by mass (A-DCP, manufactured by Shin-Nakamura Chemical Co., Ltd.)1,6-hexanediol diacrylate (LIGHT ACRYLATE 1.6HX-A, manufactured byKyoeisha Chemical Co., Ltd.) Photopolymerization initiator (IRGACURE819,  1 part by mass manufactured by BASF Corporation)

(Resin Layer Forming Step)

A resin layer was formed on the first substrate film by the followingphotoimprinting method. First, using a dispenser, the coating liquid 2for forming a resin layer was poured into a space between an SUS moldhaving a honeycomb-like pattern (in which a line width of a concaveportion is 0.5 mm, a diagonal line of a convex portion regular hexagonis 1 mm, and a concave portion depth is 50 μm) prepared by a photoetching method and the organic layer side of the first substrate film,followed by pressing thereagainst with a rubber roller at a pressure of0.3 MPa so as to discharge an excess coating liquid, so that the moldfilled with the coating liquid was laminated on the first substratefilm. Subsequently, using an air-cooled metal halide lamp (manufacturedby Eye Graphics Co., Ltd.) at 200 W/cm, ultraviolet rays at a dose of500 mJ/cm² were irradiated from the side of the first substrate film tocure the film at room temperature of 25° C., and the mold was thenreleased to obtain a first substrate film on which a resin layer wasformed.

(Phosphor Composition Filling Step)

A phosphor layer-containing film filled between the resin layers on thefirst substrate film and laminated with the second substrate film wasprepared according to the following procedure. First, using a dispenser,the coating liquid 1 of the phosphor-containing layer was poured into aspace between the resin layer side of the first substrate film on whichthe resin layer prepared in the above step was formed and the organiclayer side of the second substrate film, followed by pressingthereagainst with a rubber roller at a pressure of 0.3 MPa so as todischarge an excess coating liquid, so that the coating liquid of thephosphor-containing layer was filled between the first substrate film,the resin layer, and the second substrate film. Subsequently, using anair-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) at200 W/cm, ultraviolet rays were irradiated from the side of the firstsubstrate film at a dose of 2500 mJ/cm² to cure the film at roomtemperature of 25° C., thus preparing a phosphor-containing film. Theobtained phosphor-containing film had a resin layer width of 0.5 mm, aphosphor layer width of 1 mm, and a film thickness of each of a resinlayer and a phosphor layer of 50 μm.

Example 2

A phosphor-containing film was prepared in the same manner as in Example1, except that the composition described below was used as the coatingliquid for forming a resin layer.

<Composition of Coating Liquid 3 for Forming Resin Layer>

1,6 hexanediol diacrylate (LIGHT ACRYLATE 99 parts by mass 1.6HA-A,manufactured by Kyoeisha Chemical Co., Ltd.) Photopolymerizationinitiator (IRGACURE 819,  1 part by mass manufactured by BASFCorporation)

Comparative Example 1

A phosphor-containing film was prepared in the same manner as in Example1, except that the composition described below was used as the coatingliquid for forming a resin layer.

<Composition of Coating Liquid 4 for Forming Resin Layer>

1,9-nonanediol diacrylate (1,9ND-A, manufactured 99 parts by mass byKyoeisha Chemical Co., Ltd.) Photopolymerization initiator (IRGACURE819,  1 part by mass manufactured by BASF Corporation)

Comparative Example 2

A phosphor-containing film was prepared in the same manner as in Example1, except that the composition described below was used as the coatingliquid for forming a resin layer.

<Composition of Coating Liquid 4 for Forming Resin Layer>

Dipentaerythritol hexaacrylate (DPHA, manufactured 99 parts by mass byDaicel-Cytec Co., Ltd.) Photopolymerization initiator (IRGACURE 2022,  1part by mass manufactured by BASF Corporation)

Example 3

A phosphor-containing film was prepared in the same manner as in Example1, except that the composition described below was used as the coatingliquid for forming a resin layer.

<Composition of Coating Liquid 5 for Forming Resin Laver>

Urethane (meth)acrylate (U-4HA, manufactured 48 parts by mass byShin-Nakamura Chemical Co., Ltd.) Epoxy methacrylate (CYCLOMER M100, 25parts by mass manufactured by Daicel Chemical Industries, Ltd.)Tricyclodecanedimethanol diacrylate (A-DCP, 25 parts by massmanufactured by Shin-Nakamura Chemical Co., Ltd.) Photopolymerizationinitiator (IRGACURE 819,  1 part by mass manufactured by BASFCorporation) Photopolymerization initiator (CPI-100P,  1 part by massmanufactured by San-Apro Ltd.)

Comparative Example 3

A phosphor-containing film was prepared in the same manner as in Example1, except that the composition described below was used as the coatingliquid for forming a resin layer.

<Composition of Coating Liquid 6 for Forming Resin Layer>

Tricyclodecanedimethanol diacrylate (A-DCP, 99 parts by massmanufactured by Shin-Nakamura Chemical Co., Ltd.) Photopolymerizationinitiator (IRGACURE 819,  1 part by mass manufactured by BASFCorporation)

Example 4

A phosphor-containing film was prepared in the same manner as in Example1, except that the composition described below was used as the coatingliquid for forming a resin layer.

<Composition of Coating Liquid 8 for Forming Resin Laver>

Urethane (meth)acrylate (U-4HA, manufactured by 99 parts by massShin-Nakamura Chemical Co., Ltd.) Photopolymerization initiator(IRGACURE 2022,  1 part by mass manufactured by BASF Corporation)

Comparative Example 4

A phosphor-containing film was prepared in the same manner as in Example1, except that the composition described below was used as the coatingliquid for forming a resin layer.

<Composition of Coating Liquid 7 for Forming Resin Layer>

Trimethylolpropane triacrylate (A-TMPT, 99 parts by mass manufactured byShin-Nakamura Chemical Co., Ltd.) Photopolymerization initiator(IRGACURE 819,  1 part by mass manufactured by BASF Corporation)

Example 5

A phosphor-containing film was prepared in the same manner as in Example1, except that the total irradiation dose of ultraviolet rays in thecase of curing the resin layer was set to 50,000 mJ/cm².

Example 6

A phosphor-containing film was prepared in the same manner as in Example1, except that the total irradiation dose of ultraviolet rays in thecase of curing the resin layer was set to 500 mJ/cm².

Example 7

A phosphor-containing film was prepared in the same manner as in Example1, except that KURARISTER CI (manufactured by Kuraray Co., Ltd.) wasused as the first substrate film and the second substrate film. In thecase where the oxygen permeability of the substrate film was measuredusing OX-TRAN 2/20 (manufactured by MOCON Inc.), it showed a value of1.0×10⁻¹ cc/(m²·day·atm) or less.

<Measurement of Knoop Hardness, Creep Recovery Rate, and ElasticRecovery Rate of Resin Layer>

The Knoop hardness, creep recovery rate, and elastic recovery rate ofthe resin layer of the phosphor-containing film prepared in each Exampleand Comparative Example were respectively measured in the followingmanner.

(Knoop Hardness)

Samples similar to the resin layer of the phosphor-containing filmprepared in each Example and Comparative Example were prepared. Using aPICODENTOR HM500p type hardness tester manufactured by FischerInstruments K.K., the surface of a sample fixed to a glass substrate wasmeasured with a Knoop indenter under the conditions of a load time of 10sec, a creep time under a maximum load of 5 sec, an unloading time of 10sec, a creep time after unloading of 5 sec, and a maximum load of 20 mN.The hardness was calculated from the relationship between theindenter-sample contact area obtained from the indentation depth and themaximum load, and the average value of values at 10 points was taken asthe Knoop hardness.

(Creep Recovery Rate)

Using a PICODENTOR HM500p type hardness tester manufactured by FischerInstruments K.K., the surface of a sample fixed to a glass substrate wasmeasured with a Knoop indenter under the conditions of a load time of 10sec, a creep time under a maximum load of 5 sec, an unloading time of 10sec, a creep time after unloading of 5 sec, and a maximum load of 20 mN.The ratio of creep recovery was calculated from the relationship betweenthe indentation depth immediately after unloading and the depth after 5seconds of unloading, and the average value of values at 10 points wastaken as the creep recovery rate.

(Elastic Recovery Rate)

Using a PICODENTOR HM500p type hardness tester manufactured by FischerInstruments K.K., the surface of a sample fixed to a glass substrate ismeasured with a Knoop indenter under the conditions of a load time of 10sec, a creep time under a maximum load of 5 sec, an unloading time of 10sec, a creep time after unloading of 5 sec, and a maximum load of 20 mN.The ratio of elastic recovery is calculated from the relationshipbetween the area surrounded by three points of [indentation depth aftercreep time, maximum load], [indentation depth after creep time, zeroload], and [indentation depth immediately after unloading, zero load](corresponding to elastic deformation energy E released at unloading),and the area surrounded by four points of the origin, [indentation depthbefore creep time, maximum load], [indentation depth after creep time,maximum load], and [indentation depth after creep time, zero load](corresponding to the total energy E required for load (and creep)), onthe graph obtained by plotting the horizontal axis as an indentationdepth and the vertical axis as a load, and the average value of valuesat 10 points is taken as the elastic recovery rate.

<Measurement of Water Vapor Permeability and Oxygen Permeability ofResin Layer>

The water vapor permeability and moisture content of the resin layer ofthe phosphor-containing film prepared in each Example and ComparativeExample were measured using samples of the resin layer in the followingmanner.

(Water Vapor Permeability)

The water vapor permeability was measured by a calcium corrosion method(method described in JP2005-283561A). The conditions of the constanttemperature and humidity treatment were a temperature of 40° C. and arelative humidity of 90% RH.

(Oxygen Permeability)

With respect to oxygen permeability, fm/(s·Pa) can be used as the SIunit. It is possible to carry out conversion of units as a relationshipof 1 fm/(s·Pa)=8.752 cc/(m²·day·atm). fm is read as femtometer and 1fm=10⁻¹⁵m.

The oxygen permeability here is a value measured using an oxygen gaspermeability measuring apparatus (OX-TRAN 2/20, trade name, manufacturedby MOCON Inc.) under conditions of a measurement temperature of 23° C.and a relative humidity of 90%.

<Evaluation Items>

The phosphor-containing films prepared in Examples and ComparativeExamples were wavelength converting members, and changes over time inthe luminescence performance of these wavelength converting members weremeasured and evaluated as follows.

(Initial Luminance)

The initial luminance (Y) of the wavelength converting member of eachExample and Comparative Example was measured according to the followingprocedure.

First, each wavelength converting member was cut into a square of 1 in²using a THOMSON BLADE MIR-CI23 (manufactured by Nakayama Corporation).Each side of the cut wavelength converting member straddles the resinlayer and the fluorescent region.

On the other hand, a backlight unit was taken out by disassembling acommercially available tablet terminal (Kindle (registered trademark)Fire HDX 7″, manufactured by Amazon). After removing the wavelengthconverting member attached to the backlight unit taken out, thephosphor-containing film prepared as described above was placed on thelight guide plate, and two prism sheets whose orientations wereorthogonal to each other were laid thereon. Among the luminances of thelight emitted from a blue light source and transmitted through thephosphor-containing film and the two prism sheets, the luminance at theposition 1 mm inwards from the cut surface (however, a fluorescentregion other than the fluorescent region positioned on the cut surface)was measured with a luminance meter (SR3, manufactured by TopconCorporation) set at a position 740 mm apart in the directionperpendicular to the plane of the light guide plate, and the obtainedvalue was taken as initial luminance (Y).

The evaluation standards for the initial luminance (Y) are as follows.In the case where the evaluation result was B or higher, it can bedetermined that the luminance efficiency was maintained satisfactorily.

AA; 14000[cd/m²]<Y

A; 12000[cd/m²]<Y≤14000[cd/m²]

B; 10000[cd/m²]Y≤12000[cd/m²]

C; 8000 [cd/m²]<Y≤10000 [cd/m²]

D; 8000 [cd/m²]≥Y

(Evaluation of Edge Deterioration)

Next, each wavelength converting member was placed on a commerciallyavailable blue light source (OPSM-H150X142B, manufactured by OPTEX-FACo., Ltd.) in a room kept at 85° C., and the wavelength convertingmember was continuously irradiated with blue light for 2,000 hours.After 1,000 hours and 2,000 hours, the wavelength converting member wastaken out and the luminance thereof was measured according to the sameprocedure as above. The luminance at high temperature test 1,000 hoursand the luminance at high temperature test 2,000 hours were measured,respectively. Assuming that the luminance after the test is Y′, thechange rate (a) of the luminance (Y′) after the test relative to theinitial luminance value (Y) was calculated according to the followingexpression and evaluated as an index of luminance change according tothe following standards.

α=Y′/Y

In the case where the evaluation results were A and B, it can bedetermined that the luminance efficiency was maintained satisfactorily.Note that the evaluation result C was practically acceptable, but theevaluation result D was unacceptable. Evaluation standards for thechange rate of the luminance after the test relative to the initialluminance value were the same also in the following deteriorationevaluation.

A; 0.95<α

B; 0.7<α≤0.95

C: 0.5<α≤0.7

D; 0.5≥α

In Comparative Example 2 and Comparative Example 4, evaluation of edgedeterioration was not carried out since the cut remainder appears.

(Evaluation of Luminance Unevenness)

The wavelength converting member of each of Examples and ComparativeExamples cut into 50 mm² using a THOMSON BLADE MIR-CI 23 (manufacturedby Nakayama Corporation) and two prism sheets mounted on a commerciallyavailable tablet terminal (Kindle (registered trademark) Fire HDX 7″,manufactured by Amazon) were placed on a commercially available bluelight source (OPSM-H150X142B, manufactured by OPTEX-FA Co., Ltd.) andthe state irradiated with blue light was imaged with a single lensreflex digital camera (D-7200, manufactured by Nikon Corporation). Inthe range of 40 mm² from the sample center of the obtained image, theaverage value (G) of Gray values and the standard deviation σ wereobtained and evaluated according to the following standards. In the casewhere the evaluation results were A and B, it can be determined that theluminance unevenness was satisfactory. Note that the evaluation result Cwas practically acceptable, but the evaluation result D wasunacceptable.

A: 0%≤σ/G<3%

B: 3%≤σ/G<10%

C: 10%≤σ/G<20%

D: 20%≥σ/G

(Evaluation of Cut Surface)

Each wavelength converting member was cut into a square of 1 in² using aTHOMSON BLADE MIR-CI 23 (manufactured by Nakayama Corporation), and foursides of a square at the end face were imaged by an optical microscopeDS-Ri2 (manufactured by Nikon Corporation) and evaluated according tothe following standards.

A: No cracking on septum and no face collapse

B: Cracks generated on septum even in one of four sides

C: Face collapse even in one of four sides

(Evaluation of Cut Remainder)

Each wavelength converting member was cut into a square of 1 in² using aTHOMSON BLADE MIR-CI 23 (manufactured by Nakayama Corporation), and thepresence or absence of the cut remainder was evaluated.

The results are shown in Table 1.

TABLE 1 Resin layer Substrate film Moisture Oxygen Monomer permeabilityOxygen permeability ratio 40° C. 90% permeability UV dose[cc/day/m²/atm] Monomer [%] Initiator [g/(m²/day)] [cc/day/m²/atm][mJ/cm²] Example 1 4.0 × 10⁻³ U-4HA 49 Irg. 819 1% 284.8 3 3000 ADCP 251.6HA-A 25 Example 2 4.0 × 10⁻³ 1.6HA-A 99 Irg. 819 1% 568 18 3000Comparative 4.0 × 10⁻³ 1,9NDA 99 Irg. 819 1% 480.4 20 3000 Example 1Comparative 4.0 × 10⁻³ DPHA 99 Irg. 2022 1% 562.6 3 3000 Example 2Example 3 4.0 × 10⁻³ U-4HA 48 Irg. 819 1% 217.3 2 3000 CYCLOMER M100 25CPI-100P 1% ADCP 25 Comparative 4.0 × 10⁻³ ADCP 99 Irg. 819 1% 144.7 53000 Example 3 Example 4 4.0 × 10⁻³ U4HA 99 Irg. 2022 1% 280.2 2 3000Comparative 4.0 × 10⁻³ A-TMPT 99 Irg. 819 1% 518.3 4 3000 Example 4Example 5 4.0 × 10⁻³ U-4HA 49 Irg. 819 1% — 2.5 50000 ADCP 25 1.6HA-A 25Example 6 4.0 × 10⁻³ U-4HA 49 Irg. 819 1% — 3.5 500 ADCP 25 1.6HA-A 25Example 7 1.0 × 10⁻¹ U-4HA 49 Irg. 819 1% 284.8 3 3000 ADCP 25 1.6HA-A25 Resin layer Creep Elastic Evaluation Knoop recovery recovery Initial1000 hours 2000 hours Evaluation hardness rate rate luminance afterafter of luminance Cut Cut [N/m²] [%] [%] Y deterioration deteriorationunevenness surface remainder Example 1 200.9 19 67.8 AA A A A A AbsentExample 2 141.1 17.9 66.4 A A A A A Absent Comparative 113.8 18.3 65.1 AB C A B Absent Example 1 Comparative 290.1 20.8 85.9 — — — — A PresentExample 2 Example 3 203 15.2 63.1 A A A A A Absent Comparative 194.512.8 59.7 C A A C C Absent Example 3 Example 4 233.4 21.1 68.1 A A A A AAbsent Comparative 240.9 22.9 77.9 — — — — A Present Example 4 Example 5260.3 18.3 76.3 B A A B A Absent Example 6 162.8 19 62.3 A A B A AAbsent Example 7 200.9 19 67.8 AA A B A A Absent

From the comparison between Example 2 and Comparative Example 1, it canbe seen that, in the case where the Knoop hardness is too small, itdeteriorates at an early stage. This is thought to be because in thecase where the Knoop hardness is too small, micro scratches also occurin a direction different from the direction in which cutting is desired,thus causing cracks.

Also, from the comparison between Example 1 and Comparative Example 2,it can be seen that the cut remainder appears in the case where theKnoop hardness is too large. This is probably because the load by thecutting blade is insufficient in the case where the Knoop hardness istoo large.

Also, from the comparison between Example 3 and Comparative Example 3,it can be seen that, in the case where the elastic recovery rate is toosmall, the cut surface collapses, the initial luminance lowers, andluminance unevenness occurs. It is considered that, in the case wherethe elastic recovery rate is too small, shape recovery after cutting isdelayed, resulting in film thickness unevenness and leading to luminanceunevenness.

Further, from the comparison between Example 4 and Comparative Example4, it can be seen that, in the case where the creep recovery rate is toolarge, the cut remainder appears. It is considered that, in the casewhere the creep recovery rate is too large, the viscoelastic behaviorwill appear and the cut remainder will appear.

Further, from the comparison of Examples 1, 5 and 6, it can be seen thatKnoop hardness, creep recovery rate, and elastic recovery rate can beadjusted by appropriately setting the irradiation dose of ultravioletirradiation in the case of curing the resin layer. Further, from thecomparison between Example 1 and Example 2, it is possible to adjust thevalue of initial luminance by appropriately setting the value of oxygenpermeability.

With respect to the phosphor-containing film according to the embodimentof the present invention, the wavelength converting member has beendescribed as an example in the foregoing embodiments, but appropriateselection of the type of the phosphor can provide applications for anorganic electroluminescence layer in an organic electroluminescenceelement, an organic photoelectric conversion layer in an organic solarcell, or the like, and can achieve an effect of suppressing performancedeterioration.

EXPLANATION OF REFERENCES

-   -   1, 3, 4, 6: phosphor-containing film    -   10, 20: substrate film    -   11, 21: support film    -   12, 22: barrier layer    -   30: phosphor-containing layer    -   31, 31 a, 31 b, 31 e: phosphors    -   32: coating liquid for forming fluorescent region    -   33: binder    -   35, 35 a, 35 b: region containing phosphors (fluorescent region)    -   37: coating liquid for resin layer    -   38: resin layer having impermeability to oxygen    -   50: transfer roller    -   52, 58, 62, 68: backup roller    -   54, 64: coating part    -   56, 66: cured part    -   59: lamination film    -   60: laminating roller    -   100: wavelength converting member    -   101A: light source    -   101B: light guide plate    -   101C: planar light source    -   102: backlight unit    -   102A: reflecting plate    -   102B: retroreflective member    -   103: liquid crystal cell unit    -   104: liquid crystal display    -   110: liquid crystal cell    -   120, 130: polarizing plate    -   121, 123, 131, 133: polarizing plate protective film    -   122, 132: polarizer

What is claimed is:
 1. A phosphor-containing film comprising: a phosphor-containing layer in which a plurality of fluorescent regions, each of which contains a phosphor that deteriorates through a reaction with oxygen in the case of being exposed to oxygen, are discretely arranged and a resin layer having impermeability to oxygen is arranged among the plurality of discretely arranged fluorescent regions; and a first substrate film laminated on one main surface of the phosphor-containing layer and a second substrate film laminated on the other main surface of the phosphor-containing layer, in which the resin layer has a Knoop hardness of 115 N/mm² to 285 N/mm², a creep recovery rate of 22% or less, and an elastic recovery rate of 60% or more, and the resin layer contains a compound having the same polymerizable crosslinking group as that of the fluorescent region.
 2. The phosphor-containing film according to claim 1, wherein the curable compound forming the resin layer having impermeability to oxygen contains inorganic particles.
 3. The phosphor-containing film according to claim 2, wherein the inorganic particles are at least one selected from the group consisting of silica particles, alumina particles, zirconium oxide particles, zinc oxide particles, titanium oxide particles, mica, and talc.
 4. The phosphor-containing film according to claim 3, wherein the inorganic particles are plate-like, and an aspect ratio of the inorganic particles is 20 or more and 500 or less.
 5. A backlight unit comprising: a wavelength converting member including the phosphor-containing film according to claim 1; and at least one of a blue light emitting diode or an ultraviolet light emitting diode.
 6. A backlight unit comprising: a wavelength converting member including the phosphor-containing film according to claim 4; and at least one of a blue light emitting diode or an ultraviolet light emitting diode. 